Retrospective LLM-Based Complexity Evaluations

EIP complexity assessment

EIP-7642: eth/69 - history expiry and simpler receipts

This EIP was assessed in 2 fork contexts. Each context has its own EIP revision and information cutoff, so the scores are not interchangeable.

Prague / PectraRetrospective · Assessment cutoff 2025-04-17Osaka / FusakaRetrospective · Assessment cutoff 2025-02-21
RetrospectivePrague / PectraAssessment cutoff 2025-04-17Added after cutoffLayers: execution
LLM Completescore 14
Human Not available· Human complexity assessments were not produced for this fork; only the LLM assessment exists.

LLM assessment

Evaluated on: · Spec revision: 2025-04-17 · 0ddb8e9192

Scope at the cutoff. At the recorded cutoff, EIP-7642 introduced eth/69 by changing the eth wire-protocol Status message to advertise a node's available block range, replacing receipt transfer with a flat encoding that omits the bloom, and adding a BlockRangeUpdate notification. It also removed total difficulty from the handshake and moved the latest block hash, while retaining eth/68 as the backward-compatible alternative. The proposal explicitly did not change EVM consensus rules or require a hard fork.

14MediumMedium
Evaluator
LLMChecklist v2
Confidence
Medium
Under-specified at assessment cutoff
Yes — 4 criteria affected
Plausible range
11–15 (Low–Medium)
Assessment cutoff
2025-04-17 · EIP revision 0ddb8e9192 (2025-04-17)
Score bands · Checklist revision 2
  • Low <12
  • Medium 12–22
  • High ≥23

28 criteria scored 0–3 (4 in exceptional cases; cross-EIP interactions is uncapped); nominal maximum 84.

Complexity profile

Each segment is one criterion's contribution to the LLM total. Hover or focus a segment for its score and rationale.

Top complexity drivers

  1. Encoding changes (RLP/SSZ)3
  2. Performance risks3
  3. Security risks2
  4. Edge/boundary conditions2

Under-specified at assessment cutoff: Yes

The EIP text available at the assessment cutoff left material behavior unresolved. The affected criteria and the plausible total range record that uncertainty.

Why: The proposal does not fully define the semantics and validity of advertised range endpoints and their hash, handling of malformed or discontinuous ranges, precise BlockRangeUpdate triggers, detailed receipt-field validity, or receiver and peer-management behavior. These gaps are localized to wire interoperability and integrated sync behavior rather than EVM consensus.

Plausible total

11–15
recorded score 14 · plausible tiers Low, Medium

Unresolved questions at the cutoff (5)
  • Are earliestBlock and latestBlock inclusive, and must available history be contiguous?
  • What relationship must latestBlockHash have to latestBlock, and how should a peer handle inconsistent announcements?
  • How are an empty available range, invalid endpoint ordering, and values beyond the peer's known chain represented and handled?
  • Which range changes require BlockRangeUpdate, and what exact timing satisfies both the update recommendation and once-per-epoch limit?
  • What validation, disconnect, or penalty behavior applies to malformed receipts and range messages?
Notable ambiguities noted by the assessor (4)
  • The specification does not state whether advertised block ranges are inclusive, contiguous, or permitted to be empty.
  • The exact correspondence and validation between latestBlock and latestBlockHash is unstated.
  • The requirement to notify whenever a range changes is qualified by discretionary per-block updates and a once-per-epoch ceiling without a deterministic trigger rule.
  • The receipt layout is concise but does not specify all malformed-field and version-mismatch outcomes needed for a common negative-test baseline.

Criterion breakdown

EIP-7642 Prague / Pectra: LLM criterion scores and rationale
CriterionScoreWhy this scoreEvidence / uncertainty
Encoding changes (RLP/SSZ)3The proposal directly changes encodings at the peer interface level, which triggers the rubric's binary score-3 anchor.
  • eip.md · Specification / Status message changes, lines 50-58 eth/69 changes the ordered encoding of the Status interface, adding and removing fields and moving the block hash.
  • eip.md · Specification / Receipts message changes, lines 60-77 eth/69 replaces legacy and typed receipt transfer encodings with one flat receipt list that omits bloom.
  • eip.md · Specification / BlockRangeUpdate message, lines 79-83 A new encoded eth protocol message with range endpoints and a block hash is introduced.
Confidence: High
Performance risksUnder-specified3Validation spans serving-node regeneration, wire transfer, receiving-node reconstruction and verification, and range-aware peer fetching, so it cannot be fully benchmarked in isolation. The proposal itself describes a very large effect on existing sync bandwidth and CPU behavior, satisfying the score-3 anchor.
  • eip.md · Motivation / Removing Bloom in Receipts, lines 32-40 Existing receipt serving is described as regenerating and transferring roughly 530 GB of bloom data per sync.
  • eip.md · Rationale / Receipts changes, lines 108-121 The new encoding shifts bloom recomputation to the receiver while substantially reducing serving CPU and sync bandwidth.
  • eip.md · Motivation and Specification / BlockRangeUpdate, lines 42-46 and 79-87 Peers can alter fetching based on advertised history, while update traffic is limited to once per 32 blocks.
Confidence: Medium
Uncertainty: The EIP does not mandate a particular range-aware fetching policy or provide benchmark results for the new end-to-end path.
Security risksUnder-specified2Incorrect parsing, bloom reconstruction, hash verification, or handling of inconsistent range announcements could affect sync correctness or resource use. These risks touch a limited set of existing networking and receipt verification components and call for targeted negative testing or fuzzing, fitting score 2 rather than an extensive multi-component review.
  • eip.md · Rationale / Receipts changes, lines 108-121 Receiving nodes must reconstruct omitted bloom data to fully verify the receipt hash under the new wire representation.
  • eip.md · Motivation and Specification / BlockRangeUpdate, lines 42-46 and 79-87 Untrusted peer range announcements can influence sync-status detection and fetching behavior.
  • eip.md · Security Considerations, lines 132-134 The EIP records no explicit security considerations.
Confidence: Medium
Uncertainty: The text says there are no security considerations and does not specify validation or peer-penalty behavior for malformed or inconsistent announcements.
Edge/boundary conditionsUnder-specified2Multiple mechanisms are boundary-prone: range endpoints and their hash, protocol-version-specific layouts, receipt variants, and update cadence. The text does not establish that any one mechanism needs the elevated case count required for score 3, so the multiple-mechanism score-2 anchor fits.
  • eip.md · Specification / Status message changes, lines 50-58 The versioned Status layout adds earliest and latest block endpoints and a latest-block hash while removing and moving prior fields.
  • eip.md · Specification / Receipts message changes, lines 60-77 Receipt transfer must cover typed and legacy receipt forms, status or post-state values, and variable log lists in a new flat layout.
  • eip.md · Specification / BlockRangeUpdate message, lines 79-87 Range updates carry two endpoints and a hash and are rate-limited to at most once per 32 blocks.
Confidence: Medium
Uncertainty: Range validity, empty or discontinuous availability, endpoint inclusion, and exact notification triggers are not specified.
Unspecified behavior requiring cross-client consensusUnder-specified2Tests for malformed or inconsistent ranges, endpoint/hash relationships, receipt-field handling, and notification timing require localized agreement on outcomes that the text does not determine. The gaps are material but do not make a previously unobservable consensus behavior critical, so score 2 fits.
  • eip.md · Specification / Status message changes, lines 50-58 Range endpoints and a corresponding hash are added without normative validity, inclusion, or consistency rules.
  • eip.md · Specification / Receipts message changes, lines 60-77 A new flat receipt form is given, but detailed field validity and receiver behavior are not stated.
  • eip.md · Specification / BlockRangeUpdate message, lines 79-87 Clients should send on range updates, need not send for every block, and must remain below a once-per-epoch rate, leaving exact trigger and timing behavior open.
Confidence: High
Uncertainty: It is unclear which open details are deliberately implementation-defined rather than intended to be interoperable protocol requirements.
Patterns affecting pre-existing tests1Existing tests for the affected handshake and receipt-message paths need a limited version-specific update, but the separate eth/69 version leaves the broader and older-version test corpus intact. This fits the minor-subset anchor.
  • eip.md · Specification, lines 50-87 eth/69 changes the existing Status and Receipts layouts and adds BlockRangeUpdate.
  • eip.md · Backwards Compatibility, lines 123-128 The new wire-protocol version can coexist with eth/68, so older-version behavior remains available.
Confidence: Medium
Uncertainty: The package does not describe the organization or sharing of pre-existing eth protocol tests.
Cross-EIP interactions1The EIP has limited protocol-version interactions with EIP-5793's eth/68 baseline and the withdrawn, dependent EIP-7542 proposal. Version negotiation and coexistence deserve coordinated consideration, but eth/69 remains independently testable for the most part, fitting score 1.
  • eip.md · Front matter and Motivation, lines 1-12 and 24-30 EIP-7642 explicitly requires EIP-5793 and identifies withdrawn EIP-7542 as an earlier proposal for the history-range idea.
  • supporting/eip-5793.md · Backwards Compatibility, lines 46-50 EIP-5793 defines eth/68 as a coexisting wire-protocol version, the baseline immediately preceding eth/69.
  • supporting/eip-7542.md · Front matter and Backwards Compatibility, lines 1-11 and 48-52 The withdrawn eth/70 proposal declares EIP-7642 as a requirement and describes version coexistence with eth/69 and earlier versions.
Confidence: High
Uncertainty: EIP-7542 was withdrawn, so its interaction is documentary and version-lineage related rather than an active simultaneous deployment dependency.
Interacting EIPs: EIP-5793, EIP-7542
Show 21 zero-score criteria
Zero-score criteria (Checklist revision 2)
CriterionScoreWhy this scoreEvidence / uncertainty
Added opcodes0No opcode is introduced, matching the zero anchor.
  • eip.md · Backwards Compatibility, lines 123-130 The proposal states that it does not change EVM consensus rules.
Modified opcodes0No pre-existing opcode behavior is modified or deprecated, matching the zero anchor.
  • eip.md · Backwards Compatibility, lines 123-130 The proposal states that it does not change EVM consensus rules.
Added precompiles0No precompile is introduced, matching the zero anchor.
  • eip.md · Specification, lines 48-87 Every specified addition is an eth wire-protocol message or field.
Modified precompiles0No precompile logic or gas schedule is modified, matching the zero anchor.
  • eip.md · Backwards Compatibility, lines 123-130 The proposal is a non-consensus wire-protocol version change.
Added system contracts0No system contract is introduced, matching the zero anchor.
  • eip.md · Backwards Compatibility, lines 123-130 The EIP changes a wire-protocol version and explicitly does not change EVM consensus rules.
Modified system contracts0No existing system contract's code, state, or behavior is directly or indirectly modified, matching the zero anchor.
  • eip.md · Specification, lines 48-87 The specification is confined to peer message layouts and sending behavior.
EVM Gas rule changes0No EVM gas accounting rule is introduced or updated, matching the zero anchor.
  • eip.md · Backwards Compatibility, lines 123-130 The proposal says it changes the eth wire protocol and does not change EVM consensus rules.
State-access ordering within opcode execution0The proposal neither changes an opcode nor reorders gas charging and state access within opcode execution, matching the zero anchor.
  • eip.md · Specification, lines 48-87 All normative changes concern eth protocol message layouts and notification timing, not opcode execution.
Blob gas accounting changes0No blob-gas accounting mechanism is mentioned or modified, matching the zero anchor.
  • eip.md · Backwards Compatibility, lines 123-130 The EIP is scoped to an eth protocol version and explicitly leaves EVM consensus rules unchanged.
State gas accounting changes0There is no state-writing gas cost, state-gas budget, reservoir, or spill path change, matching the zero anchor.
  • eip.md · Backwards Compatibility, lines 123-130 The EIP changes only the eth wire protocol and requires no hard fork.
New EVM gas refund0No EVM gas-refund mechanism is introduced, matching the zero anchor.
  • eip.md · Specification, lines 48-87 The specification only changes three eth wire-protocol message surfaces.
New transaction types0Carrying the type of an existing transaction in a receipt message does not introduce a transaction type, so the zero anchor applies.
  • eip.md · Specification / Receipts message changes, lines 60-77 Existing receipt forms are represented with a tx-type element, but no new transaction type is defined.
New or modified transaction validity mechanisms0No transaction validity rule or intrinsic-gas calculation is added or modified, matching the zero anchor.
  • eip.md · Specification, lines 48-87 The normative changes concern peer message encoding and range notification, not transaction acceptance or intrinsic gas.
New block / header fields0The new interface fields do not alter the block or header schema, matching the zero anchor.
  • eip.md · Specification / Status message changes, lines 50-58 earliestBlock, latestBlock, and latestBlockHash are fields of the eth Status message, not fields of a block or block header.
Block syncing changes0Although the messages are intended to improve syncing, the rubric anchor is specifically for block-RLP validation mechanisms requiring client syncing; no such validation change is introduced. The zero anchor therefore applies.
  • eip.md · Specification, lines 50-87 The EIP changes Status and Receipts wire encodings and adds a range notification, but does not change block RLP validation.
New fork activation mechanism0There is no activation-block state or internal-variable modification, matching the zero anchor.
  • eip.md · Backwards Compatibility, lines 123-130 eth/69 is rolled out as a coexisting wire-protocol version and the EIP requires no hard fork.
Engine API changes0No Engine API endpoint, field, or communication mechanism changes, matching the zero anchor.
  • eip.md · Abstract, lines 15-20 The affected interface is the eth peer-to-peer protocol rather than the Engine API.
Transition-tool interface changes0The proposal adds no transition-tool field or mechanism, matching the zero anchor.
  • eip.md · Backwards Compatibility, lines 123-130 The change is a versioned eth wire-protocol update and explicitly requires no hard fork.
New invariant on pre-existing tests0Nothing in the text requires pre-existing tests outside this EIP's protocol surfaces to assert a new produced value, matching the zero anchor.
  • eip.md · Specification, lines 48-87 The proposal defines changed and new eth/69 messages but does not prescribe a new assertion for tests unrelated to those messages.
Uncertainty: No historical test-suite inventory is included, but the proposal itself mandates no cross-cutting assertion.
New test-framework primitives0The text establishes no need for a new framework-level expectation, modifier, or helper; ordinary protocol-message tests suffice, matching the zero anchor.
  • eip.md · Specification, lines 48-87 The specification can be expressed as message encoding, decoding, and notification behavior without defining a novel testing abstraction.
Uncertainty: The package contains no description of the historical network test framework.
Cryptography0No cryptographic primitive or cryptographic functionality is introduced or modified, matching the zero anchor.
  • eip.md · Abstract, lines 15-20 The proposal is limited to advertised history ranges, handshake simplification, and receipt-field removal.
Assessment provenance
Assessed EIP revision
ethereum/EIPs@0ddb8e9192 EIPS/eip-7642.md committed 2025-04-17 · information cutoff 2025-04-17T21:24:29Z
Current master · File history · blob 47bcbab8ac · sha256 b7d3002fa0a4
Rubric
Checklist revision 2 · ethspecs/pm@3d8c0128c5
Evaluator
gpt-5.6-sol at xhigh reasoning effort · isolation bubblewrap_one_eip_capsule_v1
Source record
Frozen research record research/tasks/05-retrospective-complexity-assignment/outputs/fork-eips/prague/eip-7642.yaml · sha256 4cdb5b15f5f2
Supporting documents in the sealed package
supporting/eip-5793.md, supporting/eip-7542.md
Compare EIP-7642 with other assessmentsAll Prague / Pectra assessments
RetrospectiveOsaka / FusakaAssessment cutoff 2025-02-21Included by cutoffLayers: execution
LLM Completescore 12
Human Not available· Human complexity assessments were not produced for this fork; only the LLM assessment exists.

LLM assessment

Evaluated on: · Spec revision: 2025-01-08 · 1632462ccf

Scope at the cutoff. EIP-7642 introduces eth/69 by removing the obsolete total-difficulty field from the Status message and omitting the bloom field from both legacy and typed receipts sent in the Receipts message. Receiving peers reconstruct a receipt bloom from its logs. The change is versioned so older peers can continue using eth/68, and the proposal expressly makes no EVM consensus change and requires no hard fork.

12MediumMedium
Evaluator
LLMChecklist v2
Confidence
Medium
Under-specified at assessment cutoff
Yes — 3 criteria affected
Plausible range
11–15 (Low–Medium)
Assessment cutoff
2025-02-21 · EIP revision 1632462ccf (2025-01-08)
Score bands · Checklist revision 2
  • Low <12
  • Medium 12–22
  • High ≥23

28 criteria scored 0–3 (4 in exceptional cases; cross-EIP interactions is uncapped); nominal maximum 84.

Complexity profile

Each segment is one criterion's contribution to the LLM total. Hover or focus a segment for its score and rationale.

Top complexity drivers

  1. Encoding changes (RLP/SSZ)3
  2. Performance risks3
  3. Edge/boundary conditions2
  4. Patterns affecting pre-existing tests1

Under-specified at assessment cutoff: Yes

The EIP text available at the assessment cutoff left material behavior unresolved. The affected criteria and the plausible total range record that uncertainty.

Why: Localized under-specification remains around receiver behavior for malformed or mixed-version receipt encodings and whether or when bloom reconstruction is mandatory. The intended happy-path schema and derivation are nevertheless clear.

Plausible total

11–15
recorded score 12 · plausible tiers Low, Medium

Unresolved questions at the cutoff (3)
  • Must an eth/69 receiver reject a receipt carrying the old bloom field, and what peer error or disconnect behavior applies?
  • Must the receiver reconstruct every bloom while decoding, before receipt verification or use, or only on demand?
  • Which malformed combinations of typed or legacy receipt payloads are valid enough to decode under eth/69?
Notable ambiguities noted by the assessor (2)
  • The manifest and output template title EIP-7642 as "eth/69 - history expiry and simpler receipts," while the sealed EIP front matter titles it "eth/69 - Drop pre-merge fields." The EIP number and sealed blob identity match, so the assessment follows the contents of that blob while preserving populated provenance.
  • The manifest labels the layer as execution, whereas the sealed EIP categorizes itself as Networking and specifies peer wire messages; the rubric is applied to that historical networking scope without changing the populated layer.

Criterion breakdown

EIP-7642 Osaka / Fusaka: LLM criterion scores and rationale
CriterionScoreWhy this scoreEvidence / uncertainty
Encoding changes (RLP/SSZ)3The ordered encoding of two peer interface messages changes. The rubric's binary encoding-change anchor assigns score 3 when an encoding change is introduced at an interface level.
  • eip.md · Specification, lines 34-64 eth/69 removes td from the Status field sequence and bloom from the receipt-data sequence used for both legacy and typed Receipts payloads.
  • eip.md · Backwards Compatibility, lines 76-80 The altered interface is deployed as a new eth wire-protocol version.
Confidence: High
Performance risks3Validating the claimed effect requires end-to-end sync behavior, including serving CPU, receiver recomputation, compression, and network transfer; it cannot be fully benchmarked in isolation and substantially changes existing sync performance. This matches score 3.
  • eip.md · Motivation, lines 22-27 Existing sync behavior is said to regenerate, transmit, and verify about 530 GB of receipt blooms per syncing peer.
  • eip.md · Rationale, lines 73-74 The proposal shifts work by reducing serving-node CPU and at least 95 GiB of compressed bandwidth while requiring receivers to recompute blooms.
Confidence: Medium
Uncertainty: The package contains estimates and qualitative CPU claims but no benchmark method or measurements with which to bound the validation work.
Edge/boundary conditionsUnder-specified2There are multiple boundary-prone mechanisms: version-specific Status field counts and version- plus receipt-form-specific Receipts decoding and bloom reconstruction. None is shown to demand an elevated case explosion, so score 2 is the best-fitting anchor.
  • eip.md · Specification, lines 34-64 Two message layouts change at the eth/68-to-eth/69 boundary, and receipt handling spans both legacy and typed forms while deriving blooms from possibly varying log lists.
  • eip.md · Backwards Compatibility, lines 76-80 Nodes may support both wire-protocol versions, creating a negotiated version boundary without a hard-fork boundary.
Confidence: Medium
Uncertainty: Malformed and mixed-version message handling is not specified, so the exact number of negative boundary cases is uncertain.
Patterns affecting pre-existing tests1Existing protocol tests for the two affected messages must use the eth/69 layouts, but this is a minor, narrow subset rather than a considerable or diverse share of pre-existing tests, matching score 1.
  • eip.md · Specification, lines 34-64 eth/69 changes the established field layouts of Status and Receipts, including both legacy and typed receipt encodings.
  • eip.md · Backwards Compatibility, lines 76-80 The changed wire format is isolated behind a new protocol version while older clients may continue using eth/68.
Confidence: Medium
Uncertainty: The package does not describe the breadth or organization of the existing networking test corpus.
Security risksUnder-specified1Incorrect encoding, decoding, or reconstruction could disrupt eth/69 peer interoperability or syncing, but the mechanism is self-contained and does not alter a chain-consensus security invariant. That fits the isolated mechanism at score 1.
  • eip.md · Backwards Compatibility, lines 76-80; Security Considerations, lines 82-84 The change is isolated behind eth/69, older peers may retain eth/68, no consensus rule changes, and the EIP records no security considerations.
  • eip.md · Specification, lines 40-64 Receivers deterministically reconstruct an omitted bloom from the logs in the received receipt.
Confidence: Medium
Uncertainty: The proposal does not specify malformed-message handling, so availability implications cannot be completely assessed from the package.
Cross-EIP interactions1The sole direct interaction is EIP-5793: EIP-7642 advances its eth/68 base protocol to eth/69. Coordinated version and regression cases are needed, but the interaction is limited and the two message changes can mostly be tested independently, matching score 1.
  • eip.md · Front matter, lines 1-12 EIP-7642 explicitly requires EIP-5793.
  • supporting/eip-5793.md · Specification, lines 26-36; Backwards Compatibility, lines 46-50 EIP-5793 defines the eth/68 predecessor message change and its coexistence with eth/67, providing the version on which eth/69 builds.
Confidence: High
Interacting EIPs: EIP-5793
Unspecified behavior requiring cross-client consensusUnder-specified1A few negative-path and reconstruction-timing details remain unstated, but the obvious intended reading is to apply the specified schema for the negotiated version and derive the existing bloom value from logs. This fits score 1 rather than a detail requiring broad redesign.
  • eip.md · Specification, lines 40-64 The happy-path eth/69 receipt shape and derivation of bloom from logs are stated, but receiver requirements and invalid or old-layout receipt handling are not expressly defined.
  • eip.md · Backwards Compatibility, lines 76-80 Multiple protocol versions may coexist, with old peers continuing to use eth/68.
Confidence: Medium
Uncertainty: The package contains no general eth protocol error-handling rules, implementation status, devnet record, or discussion record from which to determine whether those details were already shared assumptions.
Show 21 zero-score criteria
Zero-score criteria (Checklist revision 2)
CriterionScoreWhy this scoreEvidence / uncertainty
Added opcodes0No opcode is introduced, satisfying the zero anchor.
  • eip.md · Backwards Compatibility, lines 76-80 The EIP is a wire-protocol version change and expressly leaves EVM consensus rules unchanged.
Modified opcodes0No existing opcode behavior is modified or deprecated, satisfying the zero anchor.
  • eip.md · Backwards Compatibility, lines 76-80 The proposal changes the eth protocol but not EVM consensus rules.
Added precompiles0No precompile is introduced, satisfying the zero anchor.
  • eip.md · Specification, lines 32-64; Backwards Compatibility, lines 76-80 The specified scope is two networking messages with no EVM consensus change.
Modified precompiles0No precompile logic or gas schedule is modified, satisfying the zero anchor.
  • eip.md · Specification, lines 32-64; Backwards Compatibility, lines 76-80 The proposal changes networking encodings only and leaves EVM consensus rules unchanged.
Added system contracts0No system contract is introduced, satisfying the zero anchor.
  • eip.md · Specification, lines 32-64; Backwards Compatibility, lines 76-80 The proposal changes only wire-message fields and does not change EVM consensus rules.
Modified system contracts0No existing system contract code, state, or behavior is directly or indirectly modified, satisfying the zero anchor.
  • eip.md · Specification, lines 32-64; Backwards Compatibility, lines 76-80 The proposal is confined to eth wire-message representations and has no EVM consensus effect.
EVM Gas rule changes0Neither EVM execution nor any gas-accounting rule is changed, satisfying the zero anchor.
  • eip.md · Specification, lines 32-64; Backwards Compatibility, lines 76-80 The specification changes only eth protocol message fields, and the EIP expressly states that it does not change EVM consensus rules.
State-access ordering within opcode execution0No opcode execution or ordering between a state access and a gas charge is modified, satisfying the zero anchor.
  • eip.md · Specification, lines 32-64 The only specified operations remove fields from the Status and Receipts wire messages and reconstruct receipt blooms from logs.
Blob gas accounting changes0No blob-gas mechanism or value is introduced or updated, satisfying the zero anchor.
  • eip.md · Specification, lines 32-64; Backwards Compatibility, lines 76-80 The proposal is limited to networking-message encodings and disclaims an EVM consensus change.
State gas accounting changes0The proposal neither charges for state writes nor alters a state-gas budget, rate, reservoir, or spill path, satisfying the zero anchor.
  • eip.md · Specification, lines 32-64; Backwards Compatibility, lines 76-80 The specified changes concern two eth wire messages and do not change EVM consensus rules.
New EVM gas refund0No EVM gas-refund mechanism is introduced, satisfying the zero anchor.
  • eip.md · Specification, lines 32-64; Backwards Compatibility, lines 76-80 The EIP specifies only wire-message field removal and states that EVM consensus rules do not change.
New transaction types0No transaction type is introduced, satisfying the zero anchor.
  • eip.md · Specification, lines 40-64 The Receipts grammar retains the existing distinction between legacy and typed receipts and merely omits bloom from their receipt data.
New or modified transaction validity mechanisms0No transaction validity rule or intrinsic-gas calculation is added or modified, satisfying the zero anchor.
  • eip.md · Specification, lines 40-64; Backwards Compatibility, lines 76-80 Only the network representation of receipts changes, and the EIP states that EVM consensus rules are unchanged.
New block / header fields0No new block or block-header field is introduced, satisfying the zero anchor.
  • eip.md · Specification, lines 34-64 The Status schema retains existing blockhash and genesis elements while removing td, and the other change concerns receipt-message payloads.
Block syncing changes0Although the Receipts message is used in syncing, the anchor specifically concerns block RLP validation. No such validation mechanism is introduced, satisfying the zero anchor.
  • eip.md · Motivation, lines 22-27; Specification, lines 40-64 The EIP reduces data sent during sync by changing receipt-message encoding; it does not modify block RLP or block-validation encoding.
New fork activation mechanism0No state or internal variable is modified at a fork-activation block, satisfying the zero anchor.
  • eip.md · Backwards Compatibility, lines 76-80 Rollout occurs through a new negotiated wire-protocol version; the EIP expressly requires no hard fork.
Engine API changes0No Engine API endpoint, field, or communication mechanism is added or modified, satisfying the zero anchor.
  • eip.md · Specification, lines 32-64 All changes are to the peer-to-peer eth Status and Receipts messages.
Transition-tool interface changes0A state-transition tool has no new field or mechanism to expose, satisfying the zero anchor.
  • eip.md · Backwards Compatibility, lines 76-80 The EIP changes a versioned wire protocol, makes no EVM consensus change, and requires no hard fork.
New invariant on pre-existing tests0Tests of the affected message formats change their expectations, but pre-existing tests outside that scope gain no new invariant, satisfying the zero anchor.
  • eip.md · Specification, lines 34-64 The proposal replaces the expected layouts of two versioned messages; it does not specify an additional result that unrelated tests must assert.
Uncertainty: No test-suite structure is included, but the EIP states no cross-cutting assertion.
New test-framework primitives0The text gives no need for a new reusable expectation, modifier, or framework abstraction beyond ordinary encoding and decoding test cases, so existing primitives reasonably suffice.
  • eip.md · Specification, lines 34-64 The change consists of explicit old and new message schemas plus a deterministic bloom reconstruction from receipt logs.
Uncertainty: The historical test framework is not part of the sealed package.
Cryptography0No cryptographic mechanism is added or modified, satisfying the zero anchor.
  • eip.md · Abstract, lines 14-18; Specification, lines 32-64 The proposal removes two networking fields and derives an existing bloom value from receipt logs; it introduces no cryptographic primitive.
Assessment provenance
Assessed EIP revision
ethereum/EIPs@1632462ccf EIPS/eip-7642.md committed 2025-01-08 · information cutoff 2025-02-21T16:21:57Z
Current master · File history · blob 2a8835e5d9 · sha256 3a81334713cc
Rubric
Checklist revision 2 · ethspecs/pm@3d8c0128c5
Evaluator
gpt-5.6-sol at xhigh reasoning effort · isolation bubblewrap_one_eip_capsule_v1
Source record
Frozen research record research/tasks/05-retrospective-complexity-assignment/outputs/fork-eips/osaka/eip-7642.yaml · sha256 8262dd400f92
Supporting documents in the sealed package
supporting/eip-5793.md
Compare EIP-7642 with other assessmentsAll Osaka / Fusaka assessments
Criterion legend and glossary

Every stacked bar, comparison matrix, and criterion table on this site uses the same criterion colours, abbreviations, and order. Colour marks the criterion group; the abbreviation and name identify the criterion. Scores are 0–3 per criterion (4 is exceptional; cross-EIP interactions is uncapped).

EVM surface

Opcodes, precompiles, and system contracts that are added or modified.

  • Added opcodes
    Introduces new opcodes
    Score anchors
    0
    No new opcodes are introduced.
    1
    A new simple opcode is introduced (no data portion, no complex stack mechanics, and a constant gas cost).
    2
    Multiple new simple opcodes are introduced, or a single new complex opcode is introduced (has data portion, or complex stack mechanics, or a dynamic gas cost).
    3
    Multiple new opcodes are introduced, and at least one of them is complex (has data portion, or complex stack mechanics, or a dynamic gas cost).
    • Cryptography opcodes are not considered complex by default. Refer to the "Cryptography" section for a separate assessment.
  • Modified opcodes
    Modifies pre-existing opcodes
    Score anchors
    0
    No pre-existing opcode modifications are introduced.
    3
    At least one pre-existing opcode's behavior is modified (not including gas changes) or a pre-existing opcode is deprecated.
  • Added precompiles
    Introduces new precompiles
    Score anchors
    0
    No new precompiles are introduced.
    1
    A new simple precompile is introduced (constant input length, constant gas cost).
    2
    Multiple new simple precompiles are introduced, or a single new complex precompile is introduced (dynamic input length or dynamic gas cost).
    3
    Multiple new precompiles are introduced, and at least one of them is complex (dynamic input length or dynamic gas cost).
    • Cryptography precompiles are not considered complex by default. Refer to the "Cryptography" for a separate assessment.
  • Modified precompiles
    Modifies pre-existing precompiles logic or gas-accounting
    Score anchors
    0
    No pre-existing precompiles are modified.
    1
    At least one pre-existing precompile has its gas schedule modified.
    2
    Multiple pre-existing precompiles have their gas schedule modified, or a single pre-existing precompile has its behavior modified.
    3
    The behavior of multiple pre-existing precompiles, or a single complex pre-existing precompile modified.
  • Added system contracts
    Introduces new system contract, stateful or not
    Score anchors
    0
    No new system contracts are introduced.
    1
    A new system contract is introduced that is not stateful nor does it trigger a new system action (e.g. requests to the consensus layer).
    2
    Multiple new system contracts are introduced or a single new system contract that is either stateful or triggers a new system action (e.g. requests to the consensus layer).
    3
    Multiple new system contracts are introduced and at least one of them is either stateful or triggers a new system action (e.g. requests to the consensus layer).
  • Modified system contracts
    Modifies pre-existing system contracts
    Score anchors
    0
    No modifications to pre-existing system contracts are introduced, directly or indirectly.
    1
    Does not directly modify any system contract, but its behavior has minor indirect effects on one or more system contracts.
    2
    Does not directly modify any system contract, but its behavior has major indirect effects on one or more system contracts.
    3
    At least one pre-existing system contract code or state is modified, which would involve irregular state transition or a similarly complex transition methodology.

Gas and accounting

Execution, blob, and state gas rules, refunds, and where charges happen inside opcodes.

  • EVM Gas rule changes
    New EVM gas accounting rules
    Score anchors
    0
    No gas accounting changes.
    1
    Existing gas accounting mechanism is updated.
    2
    A new gas accounting mechanism is introduced but it does not affect existing mechanisms nor does it affect existing tests.
    3
    A new gas accounting mechanism is introduced and affects existing mechanisms which in turn affect existing tests.
  • State-access ordering within opcode execution · Checklist revision 2 only
    Changes *where inside an opcode's execution* state is accessed, or where gas is charged relative to that access. Because a state access is recorded in the block-level access list only if execution had enough gas to reach it, this ordering is consensus-critical: moving it changes the BAL at every gas boundary of every affected opcode.
    Score anchors
    0
    No change to where state is accessed, or to where gas is charged relative to a state access, within any opcode.
    1
    A single opcode's state-access or gas-charge ordering changes.
    2
    Multiple opcodes' ordering changes, or a new state-accessing operation is introduced whose position in the order must be settled.
    3
    The ordering rule changes for a whole class of state-accessing opcodes at once, or what counts as a recordable state access is redefined — requiring existing BAL vectors to be re-derived across opcodes and forks.
    • Distinct from "Modified opcodes", which asks whether an opcode's **result** changed. This row asks about the **path to the result**, which is observable even when the result is identical. An EIP can be 0 on that row and 3 on this one.
    • Score changes **to** the ordering. Do not score the fact that state accesses are observable — they always are.
    • Each boundary must be re-tested against every other dimension that can change the answer (cold/warm, static/non-static, delegated/direct, revert/success), so the case count grows multiplicatively rather than additively. Note this explicitly under Special Considerations.
  • Blob gas accounting changes
    New Blob gas accounting rules which potentially affect pre-existing tests
    Score anchors
    0
    No blob gas accounting changes.
    1
    Existing blob gas accounting mechanism is updated.
    2
    A new blob gas accounting mechanism is introduced but it does not affect existing mechanisms nor does it affect existing tests.
    3
    A new blob gas accounting mechanism is introduced and affects existing mechanisms which in turn affect existing tests.
  • State gas accounting changes · Checklist revision 2 only
    New state gas accounting rules. State gas is the cost of *writing* state, as opposed to accessing or executing it: `StateGasCosts`, `COST_PER_STATE_BYTE`, the block-level state gas budget, and the spill path into execution gas.
    Score anchors
    0
    No state gas accounting changes.
    1
    An existing state gas cost or `STATE_BYTES_PER_*` rate is adjusted.
    2
    A new state-gas-charging site is introduced, or the block-level state gas budget or reservoir allocation is modified.
    3
    A new state gas charging mechanism is introduced, or the spill interaction between state gas and execution gas is modified, affecting existing gas tests.
    • Harder to test than blob gas: the spill path means state gas cannot be metered independently of execution gas, and some costs (e.g. `NEW_ACCOUNT`) are state-dependent.
  • New EVM gas refund
    New gas-refund mechanism
    Score anchors
    0
    No new gas-refund mechanisms are introduced.
    1
    A new simple gas-refund mechanism is introduced that does not affect either existing tests or existing gas-refund mechanisms.
    2
    A new complex gas-refund mechanism is introduced or a simple mechanism that affects existing tests or existing gas-refund mechanisms.
    3
    A new complex gas-refund mechanism is introduced that affects existing tests or existing gas-refund mechanisms.

Blocks, transactions, and encoding

Transaction types and validity, block and header fields, encodings, syncing, and activation-time changes.

  • New transaction types
    Introduces a new transaction type
    Score anchors
    0
    No new transaction types are introduced.
    3
    A new transaction type is introduced.
  • New or modified transaction validity mechanisms
    Creates new or modifies pre-existing transaction types' validation mechanisms
    Score anchors
    0
    No changes are introduced to the validity rules of existing transaction types or to their intrinsic gas cost calculation.
    1
    Minor adjustments are introduced to validity rules or intrinsic gas cost calculation, but they do not significantly affect existing tests.
    2
    Changes to validity rules or intrinsic gas cost calculation affect existing tests, but require only limited updates to test cases and no redesign of the testing infrastructure.
    3
    Changes to validity rules or intrinsic gas cost calculation require extensive rework or redesign of the tests or testing infrastructure.
  • New block / header fields
    Introduces new block or block header fields
    Score anchors
    0
    No new block or header fields are introduced.
    3
    A new block or header field is introduced.
  • Encoding changes (RLP/SSZ)
    Introduces encoding changes at the transaction/block/interfaces level
    Score anchors
    0
    No encoding changes are introduced at the transaction, block, or interfaces levels.
    3
    An encoding change is introduced at transaction, block or interfaces level (e.g. RLP -> SSZ).
    • "Interfaces level" includes the Engine API. Score an Engine API encoding change (e.g. JSON -> SSZ) here.
  • Block syncing changes
    Modifies block RLP validation mechanisms that require test client syncing.
    Score anchors
    0
    No new RLP validation mechanism is introduced.
    1
    A single simple RLP validation mechanism is introduced.
    2
    Multiple simple RLP validation mechanisms are introduced or a single complex one.
    3
    Multiple RLP validation mechanisms are introduced and at least one of them is deemed complex.
  • New fork activation mechanism
    Modifies state, internal variables, or similar, at the fork activation block
    Score anchors
    0
    No state modifications, internal variables or similar are modified at the fork activation block.
    3
    Either a state modification or internal variables are modified at the fork activation block.
    • Initialization of new internal variable is not considered a modification.

Client interfaces

Engine API and transition-tool interface changes.

  • Engine API changes
    Introduces new fields to the Engine API directives
    Score anchors
    0
    No new fields or communication mechanisms are introduced to the Engine API.
    1
    A single new field is introduced in one of the Engine API endpoints.
    2
    Multiple fields are introduced to one or multiple Engine API end points, or a new Engine API end-point is introduced.
    3
    Multiple fields are introduced to one or multiple Engine API end points and a new Engine API end-point is introduced.
  • Engine API encoding changes · Checklist revision 1 only
    Engine API encoding changes (the revision-1 template defines no anchor text for this row).
  • Transition-tool interface changes
    Modifies or adds new fields to the transition tool interface.
    Score anchors
    0
    No modifications to the transition tool interface are required.
    1
    A single new field needs to be introduced to the transition tool interface.
    2
    Multiple new fields or a new mechanism has to be introduced to the transition tool interface.
    3
    Multiple new fields and a new mechanism has to be introduced to the transition tool interface.
    • Special consideration must be paid to this section if the EIP introduces a mechanism that requires the state transition tool to be aware whether the block it is processing is the fork-activation block.

Testing impact

Rework, new invariants, and new primitives required in the test framework.

  • Patterns affecting pre-existing tests
    Implements a new validation mechanism or rule that translates in reworking pre-existing tests
    Score anchors
    0
    No pre-existing tests are affected by this change.
    1
    Minor subset of existing tests are affected by this change.
    2
    Considerable subset of existing tests are affected by this change but involves only a contrived category of tests.
    3
    Major subset of existing tests are affected, including diverse category of tests (benchmarks, static, multiple forks, etc.).
  • New invariant on pre-existing tests · Checklist revision 2 only
    Tests that are **not about this EIP** must nonetheless assert something this EIP produces. Their logic does not change; they gain a new thing to check.
    Score anchors
    0
    Pre-existing tests assert nothing new.
    1
    A narrow, contrived category of pre-existing tests gains a new assertion.
    2
    A broad category gains a new assertion, applied mechanically.
    3
    Every test in the fork gains the assertion regardless of what it tests, and pre-fork vectors must be re-derived to satisfy it.
    • Paired with the row above, and easy to confuse with it. "Patterns affecting pre-existing tests" asks whether existing tests must be **reworked**; this row asks whether they must **additionally assert something new**. Score both — an EIP can be low on one and high on the other.
  • New test-framework primitives · Checklist revision 2 only
    Requires new abstractions in the test framework itself — expectation types, modifiers, helpers — beyond writing test functions with what already exists.
    Score anchors
    0
    Existing test primitives suffice.
    1
    Existing primitives need minor extension.
    2
    New expectation or modifier primitives are required, reusable within this EIP's own test suite.
    3
    New framework-level primitives are required that become a permanent part of the framework and are used by other EIPs' tests.

Risk and validation

Security, performance, boundary conditions, and cryptography that need validation.

  • Security risks
    Introduces or modifies mechanisms that could compromise the security of the chain, users, validators, or other stakeholders, if not implemented properly.
    Score anchors
    0
    No new mechanisms are introduced that could pose a security risk.
    1
    The introduced mechanisms are self-contained, can be validated in isolation, and do not alter existing invariants that could pose a security risk for any stakeholders.
    2
    The introduced mechanisms interact with a limited number of existing components, slightly altering their security assumptions and requiring a targeted security review or fuzzing.
    3
    The introduced mechanisms interact with multiple existing components, including critical ones, substantially altering their security assumptions and requiring an extensive security review and fuzzing.
  • Performance risks
    Introduces or modifies mechanisms and requires performance validation.
    Score anchors
    0
    No new mechanisms are introduced that require performance validation.
    1
    The introduced mechanisms can be benchmarked in isolation and do not affect existing performance behavior.
    2
    The introduced mechanisms cannot be fully benchmarked in isolation, but they only have a limited impact on the existing performance benchmarks.
    3
    The introduced mechanisms cannot be benchmarked in isolation and have a substantial impact on existing performance benchmarks or have complex interactions with existing mechanisms.
  • Edge/boundary conditions
    Feature contains edge/boundary conditions.
    Score anchors
    0
    No discernible edge cases or boundary conditions are introduced.
    1
    A single edge-case or boundary-condition prone mechanism is introduced.
    2
    Multiple edge-case or boundary-condition prone mechanisms are introduced, but none of them requires an elevated number of cases to test.
    3
    Multiple edge-case or boundary-condition prone mechanisms are introduced and at least one of them requires an elevated number of cases to test.
  • Cryptography
    Introduces new cryptography mechanisms or modifies existing functionality that involves cryptography
    Score anchors
    0
    No cryptography mechanisms are introduced.
    1
    A new cryptography mechanism is introduced but it is a well known mechanism that is known to have vast resources to aid on its testing.
    2
    Multiple new cryptography mechanisms are introduced that are well-known or a single but novel mechanism is introduced that is either untested or has limited resources.
    3
    Multiple new cryptography mechanisms are introduced and at least one of them is a novel mechanism.

Coordination

Cross-EIP interactions and behavior that clients must agree on before tests exist.

  • Cross-EIP interactions
    Introduces or modifies mechanisms that affect other EIPs in either the same or past forks.
    Score anchors
    0
    Fully self-contained EIP that does not depend on, modify, or conflict with any other EIP.
    1
    The EIP interacts with one or more other EIPs in a non-critical and limited way but can be tested independently for the most part.
    2
    The EIP depends on or modifies one or more other EIPs such that coordinated testing and consideration is required, but interactions are limited in scope and not complex.
    3
    The EIP has strong interdependencies with multiple EIPs, requiring extensive coordinated cross-EIP testing as well as potential re-design of existing test vectors.
    • +1 for every 3 additional interacting EIPs beyond the first 3, each of which requires its own coordinated test cases. List the EIPs in the rationale.
    • This row is intentionally uncapped, unlike every other anchor: each interacting EIP is another axis of the test matrix, so a ceiling would make a 12-EIP product indistinguishable from a 3-EIP one.
  • Unspecified behavior requiring cross-client consensus · Checklist revision 2 only
    The EIP text does not determine the answer for cases a test can construct. Clients must agree on a previously unspecified detail before tests can be baselined. The cost here is coordination and re-baselining, not test writing.
    Score anchors
    0
    The EIP text determines the answer for every case a test could construct.
    1
    A few details are unspecified but have an obvious intended reading.
    2
    Details require client agreement before tests can be written, but they are localized.
    3
    A previously unspecified *and previously unobservable* behavior becomes consensus-critical; expect tests to be re-baselined on each round of EIP amendment.
    • Score this from the EIP's state at assessment time: whether it has client implementations, whether it has been through a devnet, and how many open questions remain on its discussion thread.