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.

RetrospectivePrague / PectraAssessment cutoff 2025-04-17Added after cutoffLayers: execution
LLM Completescore 11
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. EIP-7642 (revision at commit 0ddb8e91) defines a new wire-protocol version, eth/69, for the 'eth' p2p protocol. It removes total difficulty (td) from the Status handshake and adds earliestBlock, latestBlock and latestBlockHash, moving the block hash to the end. It replaces the consensus receipt encoding in the Receipts (0x10) message with a flat list [tx-type, post-state-or-status, cumulative-gas, logs] that omits the Bloom field, so receivers must recompute the bloom to verify the receipt hash. It also adds a BlockRangeUpdate (0x11) notification that clients send at most once per epoch. The EIP states that it does not change EVM consensus rules and does not need a hard fork.

11LowLow
Evaluator
LLMChecklist v3
Confidence
Medium
Under-specified at assessment cutoff
Yes — 3 criteria affected
Plausible range
9–12 (Low–Medium)
Assessment cutoff
2025-04-17 · EIP revision 0ddb8e9192 (2025-04-17)
Score bands · Checklist revision 3
  • 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. Unspecified behavior requiring cross-client consensus2
  3. Patterns affecting pre-existing tests1
  4. New test-framework primitives1

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 receipt tx-type field has no type annotation, and its value for legacy transactions is not stated. Receiver behavior for invalid or overly frequent BlockRangeUpdate messages is also unspecified, and so is the response to requests outside the advertised range.

Plausible total

9–12
recorded score 11 · plausible tiers Low, Medium

Unresolved questions at the cutoff (4)
  • Is tx-type encoded as an integer (P) or a byte string, and what value do legacy receipts carry?
  • How should a node respond to BlockRangeUpdate with earliestBlock > latestBlock, or to updates sent more than once per epoch?
  • What should a node return for requests outside its advertised range?
  • Must latestBlockHash in Status be validated against latestBlock?
Notable ambiguities noted by the assessor (3)
  • The tx-type field in the eth/69 receipt list has no type annotation.
  • The once-per-epoch update limit is advisory ('should'), and the receiver's enforcement is undefined.
  • The EIP is networking-only. Whether eth-protocol hive tests count as baseline EL tests affects the PAT and FWK scores.

Criterion breakdown

EIP-7642 Prague / Pectra: LLM criterion scores and rationale
CriterionScoreWhy this scoreEvidence / uncertainty
Encoding changes (RLP/SSZ)3Three execution-client peer-message schemas change or are added: Status, Receipts and BlockRangeUpdate. This meets level 3.
  • eip.md · Status message changes The Status schema drops td, adds earliestBlock, latestBlock and latestBlockHash, and reorders fields.
  • eip.md · Receipts message changes — "receipt = [tx-type, post-state-or-status, cumulative-gas, logs]" A flat receipt list without the bloom replaces the opaque typed-receipt encoding.
  • eip.md · BlockRangeUpdate message New message schema [earliestBlock, latestBlock, latestBlockHash].
Confidence: High
Unspecified behavior requiring cross-client consensusUnder-specified2The legacy-receipt tx-type value and its encoding (integer 0 as 0x80 vs byte 0x00, or empty) are localized competing outcomes. They affect interoperability and the expected bytes in test vectors, so clients must agree before expectations can be fixed. The rules for validating and responding to BlockRangeUpdate are also omitted.
  • eip.md · Receipts message changes — "receipt = [tx-type, post-state-or-status, cumulative-gas, logs]" tx-type has no type annotation (P vs B), and its value for legacy receipts is not stated.
  • eip.md · BlockRangeUpdate message Receiver handling of invalid ranges (earliest > latest) or overly frequent updates is not specified.
Confidence: Medium
Uncertainty: These are interoperability rather than consensus outcomes, and a devp2p spec not supplied here might resolve them.
Patterns affecting pre-existing tests1State-transition and blockchain consensus fixtures are not affected. Existing peer-protocol handshake and receipt-exchange tests stay valid for eth/68. Rework is limited to Status and Receipts message construction and expectations when those tests run under eth/69, which is localized to the message-exchange family.
  • eip.md · Status message changes In eth/69 the Status handshake drops td and adds range fields, and blockhash moves to the end.
  • eip.md · Backwards Compatibility — "they can keep using protocol version eth/68" eth/68 stays supported side by side, so eth/68 tests remain valid.
Confidence: Low
Uncertainty: Whether eth-protocol hive/devp2p tests count as baseline EL tests, and whether the suite will be migrated to eth/69 rather than duplicated, decides between 0 and 2.
New test-framework primitives1Peer-protocol test harnesses need a local extension: an eth/69 capability, the new message codecs, and handling of an unsolicited notification. These are new message types within an existing kind of primitive (devp2p message exchange), not a shared new abstraction.
  • eip.md · Specification Requires eth/69 Status and Receipts codecs and a new BlockRangeUpdate (0x11) message.
Confidence: Medium
Uncertainty: Checking unsolicited, rate-limited BlockRangeUpdate announcements over time could need a new expectation abstraction (level 2).
Security risksUnder-specified1Local checks are enough: receipts received without a bloom must still be verified against the receipt root, and malformed or false range announcements must be handled. No other component's assumptions change.
  • eip.md · Security Considerations — "None" The EIP claims no security considerations.
  • eip.md · Receipts changes — "recompute the bloom filter in order to fully verify the receipt hash" The receipt validation boundary changes: data from peers must be rebuilt locally before verification.
Confidence: Medium
Uncertainty: Peers can falsely advertise ranges, and the spec gives no rule for handling them.
Performance risks1Receipt serving and receiving workloads change: no bloom regeneration on the server, recomputation on the receiver. A component benchmark of receipt encode/verify throughput covers this without changing end-to-end assumptions.
  • eip.md · Receipts changes — "The recomputation is not very CPU intensive" Bloom-recomputation CPU moves from serving nodes to receiving nodes, in exchange for roughly 530GiB less bandwidth.
Confidence: Low
Uncertainty: The change is intended to reduce load, and the claimed CPU cost is not quantified. The score could be 0.
Edge/boundary conditionsUnder-specified1One boundary-sensitive mechanism is introduced: advertising the block range and updating it at most once per 32 blocks.
  • eip.md · BlockRangeUpdate message — "at most once per epoch (32 blocks)" The rate bound depends on the advance of block-range boundaries.
  • eip.md · Status message changes — earliestBlock, latestBlock The advertised range sets which history requests a peer can serve.
Confidence: Low
Uncertainty: The rate limit is advisory ('should') and the receiver's response to violations is unspecified, so the score could be 0.
Cross-EIP interactions1Only local compatibility checks are needed: negotiating eth/68 and eth/69 side by side, and confirming that eth/68's announcement format remains unchanged under eth/69. EIP-7542 is withdrawn and does not interact.
  • eip.md · Status message changes — "(eth/68): ..." eth/69 is defined as a delta from the eth/68 Status message.
  • supporting/eip-5793.md · Specification eth/68 changes NewPooledTransactionHashes, and that message is carried into eth/69.
  • supporting/eip-7542.md · status: Withdrawn The withdrawn proposal is cited only as motivation.
Confidence: Medium
Uncertainty: Receipt encoding across all typed transaction types (EIP-2718-based) needs a conversion back to the consensus encoding to verify the root. Here that is treated as a local encoding check.
Interacting EIPs: EIP-5793
Show 20 zero-score criteria
Zero-score criteria (Checklist revision 3)
CriterionScoreWhy this scoreEvidence / uncertainty
Added opcodes0None.
  • eip.md · Backwards Compatibility No EVM changes.
Modified opcodes0None.
  • eip.md · Backwards Compatibility No EVM changes.
Added precompiles0None.
  • eip.md · Backwards Compatibility No EVM changes.
Modified precompiles0None.
  • eip.md · Backwards Compatibility No EVM changes.
Added system contracts0None.
  • eip.md · Specification No contracts are introduced.
Modified system contracts0None.
  • eip.md · Specification No contracts are involved.
EVM Gas rule changes0No execution-gas charging, metering or limit rule changes.
  • eip.md · Backwards Compatibility — "does not change consensus rules of the EVM" The change is limited to the networking protocol and does not touch execution gas.
State-access ordering within opcode execution0No opcode's state-access or gas-charge ordering changes.
  • eip.md · Specification The only changes are to the Status, Receipts and BlockRangeUpdate p2p messages. No instruction is involved.
Blob gas accounting changes0No blob-gas accounting changes.
  • eip.md · Backwards Compatibility — "does not require a hard fork" No consensus changes, including none to blob gas.
State gas accounting changes0No state-gas accounting changes.
  • eip.md · Backwards Compatibility No EVM consensus rule changes.
New EVM gas refund0No refund mechanism is introduced.
  • eip.md · Backwards Compatibility No EVM consensus rule changes.
New transaction types0None.
  • eip.md · Specification No transaction envelope is introduced.
New or modified transaction validity mechanisms0None.
  • eip.md · Backwards Compatibility No consensus rule changes.
New block / header fields0No block or header member is added.
  • eip.md · Receipts changes — "the networking protocol now deviates from the encoding used by consensus" The consensus receipt and header schemas are unchanged. Only the p2p messages change.
Block syncing changes0The receipt download format changes, but block RLP decoding and block structural validation do not. Other sync work falls outside this criterion.
  • eip.md · Receipts message changes Only the p2p receipt encoding changes. Execution-block RLP and structural validation are unchanged.
Uncertainty: Receipt-hash verification after recomputing the bloom during sync could be read as a changed sync validation rule (level 1).
New fork activation mechanism0No activation-specific state transition.
  • eip.md · Backwards Compatibility — "does not require a hard fork" Rolled out by protocol version negotiation, not by fork activation.
Engine API changes0No Engine API changes.
  • eip.md · Specification Only eth wire-protocol messages change.
Transition-tool interface changes0The transition-tool inputs and outputs do not change. Consensus receipts still include the bloom.
  • eip.md · Backwards Compatibility — "does not change consensus rules of the EVM" State transition is unchanged.
New invariant on pre-existing tests0Baseline tests need no new assertion on any consensus output.
  • eip.md · Backwards Compatibility No new consensus outputs such as header or receipt fields. The bloom is removed only on the wire.
Cryptography0Unchanged primitives are reused, so no cryptographic mechanism changes. The changed message bytes belong under encoding.
  • eip.md · Receipts changes — "The receiving nodes will need to recompute the bloom filter in order to fully verify the receipt hash" Verification reuses the existing bloom construction and the receipt-root hashing.
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 3 · ethspecs/pm@fe2f793b03
Evaluator
Opus 5.5 (claude-opus-5-5) at high effort, one tool-less call per EIP · isolation bubblewrap_claude_p_no_tools_v1
Source record
Frozen research record research/tasks/10-opus-v3-reassessment/retrospective/outputs/assessments/prague/eip-7642.yaml · sha256 98ee7624be09
Supporting documents supplied with the EIP
supporting/eip-5793.md, supporting/eip-7542.md
RetrospectiveOsaka / FusakaAssessment cutoff 2025-02-21Included by cutoffLayers: execution
LLM Completescore 8
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 defines a new devp2p wire protocol version, eth/69. It removes the `td` field from the `Status (0x00)` handshake message and drops the `bloom` field from legacy and typed receipts in the `Receipts (0x10)` message. Receiving nodes recompute blooms from the logs. The EIP says it changes no EVM consensus rules and needs no hard fork. Older clients can keep using eth/68, which is defined by the prerequisite EIP-5793.

8LowLow
Evaluator
LLMChecklist v3
Confidence
High
Under-specified at assessment cutoff
Yes — 3 criteria affected
Plausible range
6–10 (Low)
Assessment cutoff
2025-02-21 · EIP revision 1632462ccf (2025-01-08)
Score bands · Checklist revision 3
  • 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. New test-framework primitives1
  3. Security risks1
  4. Performance risks1

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 eth/69 typed receipt-data layout is described only as 'omit the bloom', not written out. The EIP gives no procedure for verifying bloom-less receipts against the receipts root, and does not describe Status handshake handling without TD. The intended outcomes are reasonably clear.

Plausible total

6–10
recorded score 8 · plausible tiers Low

Unresolved questions at the cutoff (3)
  • What is the exact eth/69 receipt-data layout for each typed receipt?
  • How must a receiver verify bloom-less receipts against the header receiptsRoot, and how should it handle mismatches?
  • How should eth/69 peers judge sync status without TD (forkid only)?
Notable ambiguities noted by the assessor (3)
  • The title in the task framing ('history expiry and simpler receipts') differs from this revision's title ('Drop pre-merge fields'). Only the TD and bloom removals are assessed.
  • The networking-only scope means most EL consensus-test criteria do not apply; the testing burden falls on devp2p/hive-style protocol testing.
  • Security Considerations states 'None', even though the receipt validation path on the receiving node changes.

Criterion breakdown

EIP-7642 Osaka / Fusaka: LLM criterion scores and rationale
CriterionScoreWhy this scoreEvidence / uncertainty
Encoding changes (RLP/SSZ)3Two execution-client peer-message schemas change: Status drops `td`, and the receipt list entries in Receipts drop `bloom`. The rubric lists execution-client peer messages as covered interfaces (level 3).
  • eip.md · Specification — "(eth/69): [version: P, networkid: P, blockhash: B_32, genesis: B_32, forkid]" The Status peer message schema loses the td field.
  • eip.md · Specification — eth/69 legacy-receipt without bloom The Receipts (0x10) peer message receipt encoding removes bloom from legacy and typed receipts.
Confidence: High
New test-framework primitivesUnder-specified1Peer-protocol test tooling needs a local extension: an eth/69 message codec, bloom-less receipt serialization and version negotiation. Existing kinds of devp2p message primitives would be extended rather than a new shared abstraction created (level 1).
  • eip.md · Specification — "We omit the bloom filter from both the legacy and typed receipts" Testing requires constructing and checking a networking receipt encoding without bloom, plus a Status message without td.
Confidence: Low
Uncertainty: No supplied evidence describes the networking test harness. If no devp2p message-testing primitive exists in the baseline, a new abstraction could be needed; if receipts tooling already supports arbitrary encodings, no extension may be required.
Security risksUnder-specified1The receiving node's validation of peer-supplied receipts changes. It must reconstruct the consensus receipt (with bloom) and check it against the header's receipts root, and it must reject malformed or mismatching receipts. This check is local to the p2p receipt handler (level 1).
  • eip.md · Security Considerations — "None" Authors claim no security considerations.
  • eip.md · Specification — "Receiving nodes will be able to recompute the bloom filter based on the logs" Peer-supplied receipts no longer include bloom, so the receiver must derive it before validating against the receipts root.
Confidence: Low
Uncertainty: The EIP gives no validation procedure. Removing td from Status may also affect peer-selection heuristics, though the rationale says forkid suffices.
Performance risks1The changed workload is bloom recomputation by the receiver for every downloaded receipt. Component benchmarks of receipt decoding plus bloom computation can check the 'not very CPU intensive' claim and the bandwidth savings. Baseline end-to-end assumptions do not change (level 1).
  • eip.md · Rationale — "The receiving nodes will need to recompute the bloom filter. The recomputation is not very CPU intensive." CPU work for bloom generation moves from the serving node to the receiving node during receipt sync.
  • eip.md · Rationale — "roughly 530GiB per syncing node" Large bandwidth reduction claimed.
Confidence: Medium
Uncertainty: The EIP gives no measurements to support the CPU claim. Arguably no validation is needed beyond confirming the claim (level 0).
Cross-EIP interactions1The interaction with EIP-5793 (eth/68) needs only local compatibility checks. Peers negotiating eth/68 and eth/69 must use the matching Status and Receipts encodings, and the eth/68 NewPooledTransactionHashes format must still apply under eth/69. No coordinated cross-EIP scenarios are required (level 1).
  • eip.md · Backwards Compatibility — "they can keep using protocol version eth/68" eth/69 must coexist with eth/68 through protocol-version negotiation.
  • supporting/eip-5793.md · Specification — NewPooledTransactionHashes (eth/68) eth/68 defines the baseline eth protocol that eth/69 builds on; that message is not changed by eth/69.
Confidence: Medium
Uncertainty: Typed receipts (EIP-2718-style tx-type || receipt-data) are referenced without an EIP number. No supplied document defines that scheme.
Interacting EIPs: EIP-5793
Unspecified behavior requiring cross-client consensus1The eth/69 typed-receipt payload is not written out, but the surrounding text supports one intended outcome: the same fields minus bloom. Peer handling without TD is not described, but no competing normative interpretation arises. This is a localized omission (level 1).
  • eip.md · Specification — "We omit the bloom filter from both the legacy and typed receipts" The eth/69 typed receipt-data layout is described only by reference to the legacy layout, not written out explicitly.
  • eip.md · Specification — Status (eth/69) No stated handshake behavior regarding td-based peer judgement or validation of the remaining fields.
Confidence: Medium
Uncertainty: The outcome concerns peer interoperability, not block consensus.
Show 22 zero-score criteria
Zero-score criteria (Checklist revision 3)
CriterionScoreWhy this scoreEvidence / uncertainty
Added opcodes0No new instructions.
  • eip.md · Backwards Compatibility — "does not change consensus rules of the EVM" No EVM changes.
Modified opcodes0No instruction semantics change.
  • eip.md · Backwards Compatibility — "does not change consensus rules of the EVM" No EVM changes.
Added precompiles0No new precompiles.
  • eip.md · Specification No precompiles introduced.
Modified precompiles0No precompile changes.
  • eip.md · Specification No precompile changes.
Added system contracts0No system contracts.
  • eip.md · Specification No contracts introduced.
Modified system contracts0No system contract changes.
  • eip.md · Specification No contract-related changes.
EVM Gas rule changes0Only peer messages change; execution-gas accounting is untouched (level 0).
  • eip.md · Backwards Compatibility — "does not change consensus rules of the EVM" Explicitly states no EVM consensus rule change, so no gas accounting changes.
State-access ordering within opcode execution0No opcode state-access or gas-charge ordering is affected.
  • eip.md · Specification Only Status and Receipts wire-message encodings are modified; no instruction behavior.
Blob gas accounting changes0No blob-gas rules are touched.
  • eip.md · Backwards Compatibility — "does not require a hard fork" No consensus changes, hence no blob-gas accounting changes.
State gas accounting changes0No state-gas accounting is affected.
  • eip.md · Backwards Compatibility No EVM consensus change.
New EVM gas refund0No refund mechanism is introduced.
  • eip.md · Specification Only networking message formats change.
New transaction types0No new transaction types.
  • eip.md · Specification No transaction envelope introduced.
New or modified transaction validity mechanisms0Transaction validity is untouched.
  • eip.md · Backwards Compatibility — "does not require a hard fork" No consensus validity rules change.
New block / header fields0No EL block or header member is added.
  • eip.md · Specification Header and block schema unchanged; only peer messages change.
Block syncing changesUnder-specified0Block RLP and block import validation are unchanged. The receipts exchange is a peer message outside block decoding, and the rubric excludes non-block synchronization work.
  • eip.md · Motivation — "a syncing node will ask for the Bloom filters for all receipts" The change affects receipt download over p2p, not execution-block RLP decoding or block structural validation.
Uncertainty: A syncing node must recompute blooms to verify downloaded receipts against the header's receipts root. Under a broad reading this could count as one simple sync validation change (level 1).
New fork activation mechanism0No activation-specific EL state transition.
  • eip.md · Backwards Compatibility — "does not require a hard fork" Rollout happens through protocol-version negotiation, not a fork transition.
Engine API changes0No Engine API field or endpoint changes.
  • eip.md · Specification Only eth wire messages are modified; no Engine API content.
Transition-tool interface changes0The t8n interface needs no change.
  • eip.md · Backwards Compatibility — "does not change consensus rules of the EVM" State transition is unchanged; receipts output by t8n still contain the consensus bloom.
Patterns affecting pre-existing tests0Consensus test vectors and eth/68 protocol behavior stay the same. New eth/69 tests are new feature tests, not rework of baseline tests.
  • eip.md · Backwards Compatibility — "they can keep using protocol version eth/68" eth/68 remains valid; eth/69 is an additional version, so baseline behavior is unchanged.
New invariant on pre-existing tests0Baseline tests need no additional assertion.
  • eip.md · Specification No new block, header, receipt-consensus or log output is introduced; the consensus receipt (with bloom) is unchanged.
Edge/boundary conditions0No boundary-sensitive rule is introduced or changed.
  • eip.md · Specification Field removals only; no new numeric bounds or limits.
Uncertainty: Receipts with zero logs (empty bloom) are a natural test case, but they are not a changed boundary rule.
Cryptography0No cryptographic mechanism or validation rule changes. Bloom recomputation and receipts-root hashing use unchanged primitives.
  • eip.md · Specification — "Receiving nodes will be able to recompute the bloom filter based on the logs" Bloom recomputation reuses the existing unchanged bloom construction; no new cryptographic rule.
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 3 · ethspecs/pm@fe2f793b03
Evaluator
Opus 5.5 (claude-opus-5-5) at high effort, one tool-less call per EIP · isolation bubblewrap_claude_p_no_tools_v1
Source record
Frozen research record research/tasks/10-opus-v3-reassessment/retrospective/outputs/assessments/osaka/eip-7642.yaml · sha256 c4b69f4c56f8
Supporting documents supplied with the EIP
supporting/eip-5793.md
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 · not in checklist revision 1
    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 · not in checklist revision 1
    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 · not in checklist revision 1
    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 · not in checklist revision 1
    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 · not in checklist revision 1
    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.