Retrospective LLM-Based Complexity Evaluations

EIP complexity assessment

EIP-7251: Increase the MAX_EFFECTIVE_BALANCE

Assessed in Prague / Pectra. The score describes the EIP text available at the assessment cutoff, not the EIP as it stands today.

RetrospectivePrague / PectraAssessment cutoff 2024-03-21Included by cutoffLayers: execution, consensus
LLM Completescore 19
Human Not available· Human complexity assessments were not produced for this fork; only the LLM assessment exists.

LLM assessment

Evaluated on: · Spec revision: 2024-01-31 · faccff3ac9

Scope at the cutoff. At the cutoff, this draft proposed raising MAX_EFFECTIVE_BALANCE to 2048 ETH while retaining a 32 ETH activation minimum, with variable-balance validators and compounding withdrawal credentials. Its consensus-layer sketch also proposed validator consolidation, configurable partial-withdrawal ceilings, balance-weighted deposit and exit churn, pending balance deposits, weight-aware aggregator selection, and related withdrawal changes; removal of the initial slashing penalty remained under discussion. It stated that EIP-7251 itself required no execution-layer changes, while depending on EIP-7002 for execution-triggered partial withdrawals.

19MediumMedium
Evaluator
LLMChecklist v2
Confidence
Medium
Under-specified at assessment cutoff
Yes — 10 criteria affected
Plausible range
15–25 (Medium–High)
Assessment cutoff
2024-03-21 · EIP revision faccff3ac9 (2024-01-31)
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. Patterns affecting pre-existing tests3
  3. Security risks3
  4. Performance risks3

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: Material consensus behavior is unresolved: the document is a change sketch without complete data types or transition rules for consolidation, custom withdrawal ceilings, pending deposits, balance-weighted churn, and activation. The proposed slashing change remains in discussion, and the packaged EIP-7002 revision specifies execution-triggered exits rather than the partial withdrawals EIP-7251 assigns to it.

Plausible total

15–25
recorded score 19 · plausible tiers Medium, High

Unresolved questions at the cutoff (7)
  • What exact messages, authorization rules, state transitions, and queue rules perform validator consolidation?
  • How is a validator's custom effective-balance or partial-withdrawal ceiling represented, authorized, updated, and bounded?
  • What are the complete PendingDeposit and BeaconState field definitions, and what are the ordering and failure semantics of pending-deposit processing?
  • How are balance-based activation and exit churn computed at boundaries and when deposits, withdrawals, exits, and consolidations compete?
  • What activation-time initialization or migration applies to new fields and existing validators?
  • Is the initial slashing penalty removed, and if so what replacement rule applies?
  • How does EIP-7002 carry and validate a partial-withdrawal amount when its packaged revision only defines full exit requests?
Notable ambiguities noted by the assessor (4)
  • EIP-7251 says it makes no execution-layer changes yet makes execution-triggered partial withdrawals a defining feature supplied by EIP-7002; direct execution changes were scored zero and the dependency was scored under cross-EIP interactions.
  • The packaged EIP-7002 revision specifies execution-triggered exits, not the partial-withdrawal amount and validation semantics that EIP-7251 expects.
  • Removal of the initial slashing penalty is listed as a defining feature but marked still in discussion, so it was treated as unresolved scope rather than a settled rule.
  • The rubric's encoding anchor was applied to the added PendingDeposit container and BeaconState fields as a consensus-layer SSZ schema change, although the draft omits their exact definitions.

Criterion breakdown

EIP-7251 Prague / Pectra: LLM criterion scores and rationale
CriterionScoreWhy this scoreEvidence / uncertainty
Encoding changes (RLP/SSZ)Under-specified3Adding a consensus container and BeaconState fields changes the consensus-layer SSZ schema, which is an encoding change and therefore triggers the rubric's binary score-3 anchor.
  • eip.md · Specification — Consensus layer change sketch, lines 49-51 The proposal creates a PendingDeposit container and adds deposit- and exit-rate-limiting fields to BeaconState.
Confidence: Medium
Uncertainty: The revision does not define the container fields or enumerate the exact BeaconState additions.
Patterns affecting pre-existing testsUnder-specified3The changes span diverse existing consensus-test categories rather than a contrived subset, so a major body of pre-existing tests would need reworking under the score-3 anchor.
  • eip.md · Specification — Consensus layer change sketch, lines 49-68 The sketch changes consensus constants and BeaconState fields, activation eligibility, deposit handling, activation and exit churn, registry processing, aggregation selection, weak-subjectivity computation, withdrawal credentials, and withdrawal eligibility.
  • eip.md · Backwards Compatibility, lines 86-88 The proposal declares backward-incompatible changes to the consensus block-validation rule set requiring a hard fork.
Confidence: Medium
Uncertainty: The document is only a change sketch, so the exact affected-test count cannot be derived.
Security risksUnder-specified3If implemented incorrectly, the mechanisms touch multiple critical consensus and validator-fund components—committee selection, aggregation, churn, withdrawals, and slashing—so they require broad security review and meet score 3 despite the proposal's intended preservation of security.
  • eip.md · Security Considerations, lines 90-112 The proposal analyzes committee takeover, weight-aware aggregator selection, proposer and sync-committee selection, and activation and exit churn invariants.
  • eip.md · Specification — Defining features, lines 41-45 The scope also includes consolidation, custom partial withdrawals, and a still-discussed removal of the initial slashing penalty.
Confidence: Medium
Uncertainty: The slashing change remained unsettled, and the security section asserts limited impact without fully specifying the mechanisms.
Performance risksUnder-specified3Network, aggregation, state-memory, proposer-selection, and queue behavior interact with existing validator workloads and cannot be validated fully in isolation; the breadth and interaction with existing benchmarks meet score 3.
  • eip.md · Motivation, lines 19-21 The proposal aims to change validator-set size and thereby P2P message volume, BLS aggregation work, BeaconState memory, and beacon-node operation.
  • eip.md · Security Considerations — Proposer selection probability, lines 102-104 The text expects lower selection probabilities to make next-proposer-index calculation slightly slower.
  • eip.md · Security Considerations — Churn invariants, lines 110-112 Activation, exit churn, and balance top-ups move to active-weight-based handling and shared queue constraints.
Confidence: Medium
Uncertainty: The text gives expected directions but no benchmark design or quantitative performance bounds.
Edge/boundary conditionsUnder-specified3Multiple interacting threshold, queue, credential, consolidation, and withdrawal mechanisms create a multiplicative set of boundary cases, including exact balance limits and competing validator lifecycle states; this meets score 3.
  • eip.md · Specification — Constants and defining features, lines 25-45 The proposal introduces distinct 32 ETH activation and 2048 ETH effective-balance bounds, consolidation, custom partial-withdrawal ceilings, execution-triggered partial withdrawals, and a debated slashing change.
  • eip.md · Specification — Consensus layer change sketch, lines 49-68 It adds pending-deposit processing, balance-rate-limited activation and exit queues, a new credential prefix, and full, partial, and excess-balance withdrawal checks.
Confidence: High
Uncertainty: The precise boundary semantics are not fully specified, which is scored separately as under-specification.
Cross-EIP interactionsUnder-specified2The direct EIP-7002 dependency requires coordinated execution/consensus testing and interface agreement, but only one identified interaction is in scope, fitting score 2 rather than the multiple-EIP score-3 anchor.
  • eip.md · Front matter, lines 1-12 The proposal formally requires EIP-7002.
  • eip.md · Specification and Rationale — EIP-7002 partial withdrawals, lines 41-45 and 81-82 EIP-7251 relies on EIP-7002 for execution-layer messages that trigger partial withdrawals from variable-balance validators.
  • supporting/eip-7002.md · Consensus layer, lines 282-291 The dependency crosses layers through operations carried in ExecutionPayload and consensus processing, while this packaged revision describes exits rather than the partial-withdrawal extension EIP-7251 expects.
Confidence: High
Uncertainty: The sealed EIP-7002 revision does not yet contain the partial-withdrawal behavior attributed to it by EIP-7251.
Interacting EIPs: EIP-7002
Unspecified behavior requiring cross-client consensusUnder-specified2Multiple consensus answers must be agreed before deterministic vectors can be written, but the package does not establish the score-3 condition of a previously unobservable behavior newly becoming consensus-critical; score 2 is therefore the closest anchor.
  • eip.md · Specification — Defining features and change sketch, lines 39-68 The revision labels its function list a sketch and does not define consolidation mechanics, custom-ceiling representation and updates, the PendingDeposit fields, the new BeaconState fields, or complete transition pseudocode.
  • eip.md · Specification — Defining features, lines 43-45 Execution-triggered partial withdrawals are delegated to EIP-7002, while removal of the initial slashing penalty is explicitly still in discussion.
  • supporting/eip-7002.md · Consensus layer, lines 282-291 The packaged EIP-7002 revision only sketches execution-triggered exits and does not specify the partial-withdrawal behavior expected by EIP-7251.
Confidence: High
Uncertainty: The omissions are broad rather than cleanly localized, while the rubric's score-3 trigger is not clearly demonstrated.
Show 21 zero-score criteria
Zero-score criteria (Checklist revision 2)
CriterionScoreWhy this scoreEvidence / uncertainty
Added opcodes0No opcode is added, satisfying score 0.
  • eip.md · Specification — Execution layer, lines 33-35 The proposal explicitly excludes execution-layer changes.
Modified opcodes0No pre-existing opcode behavior is changed or deprecated, satisfying score 0.
  • eip.md · Specification — Execution layer, lines 33-35 The proposal explicitly excludes execution-layer changes.
Added precompiles0The assigned EIP adds no precompile of its own; attributing the dependency's precompile here would double-count the cross-EIP interaction, so score 0 applies.
  • eip.md · Specification — Execution layer, lines 33-35 EIP-7251 states that it requires no execution-layer changes.
  • supporting/eip-7002.md · Abstract, lines 13-17 The stateful precompile is introduced by the separately identified EIP-7002 dependency.
Modified precompiles0No existing precompile logic or gas schedule is modified by EIP-7251, matching score 0.
  • eip.md · Specification — Execution layer, lines 33-35 The proposal explicitly excludes execution-layer changes.
Added system contracts0EIP-7251 directly adds no system contract, so score 0 applies; the separate EIP-7002 mechanism is captured under cross-EIP interactions.
  • eip.md · Specification — Execution layer, lines 33-35 The proposal states that EIP-7251 requires no execution-layer changes.
  • eip.md · Specification — Defining features, lines 41-45 Execution-layer partial withdrawals are assigned to EIP-7002 rather than specified as a new EIP-7251 system contract.
Modified system contracts0No pre-existing system-contract code, state, or behavior is directly or indirectly modified by the assigned EIP, matching score 0.
  • eip.md · Specification — Execution layer, lines 33-35 The proposal explicitly requires no execution-layer changes.
Uncertainty: The interaction with EIP-7002 is scored separately and is not described as modification of a pre-existing deployed system contract.
EVM Gas rule changes0No EVM gas accounting rule is introduced or updated, satisfying the zero anchor.
  • eip.md · Specification — Execution layer, lines 33-35 The proposal explicitly states that it requires no changes to the execution layer.
State-access ordering within opcode execution0With no opcode or execution-layer change, it does not alter state-access or gas-charge ordering inside any opcode, matching score 0.
  • eip.md · Specification — Execution layer, lines 33-35 The proposal explicitly excludes execution-layer changes.
Blob gas accounting changes0No blob gas accounting mechanism is described, so the zero anchor applies.
  • eip.md · Specification — Execution layer, lines 33-35 The proposal explicitly states that it requires no execution-layer changes.
State gas accounting changes0Consensus validator balances and churn are not the rubric's state-gas mechanism, and no state-gas cost, rate, budget, or spill rule is changed.
  • eip.md · Specification — Execution layer, lines 33-35 The proposal explicitly states that it requires no execution-layer changes.
New EVM gas refund0No EVM refund mechanism is introduced, matching score 0.
  • eip.md · Specification — Execution layer, lines 33-35 The proposal explicitly excludes execution-layer changes.
New transaction types0No transaction type is introduced, so score 0 applies.
  • eip.md · Specification — Execution layer, lines 33-35 The proposal states that it requires no execution-layer changes.
New or modified transaction validity mechanisms0It does not change transaction validity or intrinsic gas calculation, matching score 0.
  • eip.md · Specification — Execution layer, lines 33-35 The proposal explicitly states that no execution-layer changes are required.
New block / header fields0No new EIP-7251 block or header field is specified, so the binary zero anchor applies.
  • eip.md · Specification — Execution layer, lines 33-35 EIP-7251 directly requires no execution-layer changes.
  • eip.md · Specification — Consensus layer change sketch, lines 49-68 The listed direct consensus changes concern BeaconState and processing helpers, not a new block or header field.
Uncertainty: The EIP-7002 dependency has its own block fields, which are accounted for as an interaction rather than a direct EIP-7251 field.
Block syncing changes0It introduces no execution block RLP-validation mechanism requiring client syncing, so score 0 applies.
  • eip.md · Specification — Execution layer, lines 33-35 The assigned EIP explicitly requires no execution-layer change.
Uncertainty: EIP-7002 has separate block-structure changes; those are treated as a cross-EIP dependency rather than direct EIP-7251 scope.
New fork activation mechanismUnder-specified0Requiring fork activation is not itself the rubric trigger; absent a specified one-time modification of existing state or variables at activation, score 0 is best supported.
  • eip.md · Backwards Compatibility, lines 86-88 The changes require a hard fork, but the document does not specify a one-time state or existing-variable modification at the activation block.
  • eip.md · Specification — Consensus layer change sketch, lines 49-51 The sketch adds constants, a new container, and new BeaconState fields without defining an activation-time migration.
Uncertainty: The revision does not explain initialization or migration of the new BeaconState fields or treatment of existing validators at activation.
Engine API changes0No Engine API field, endpoint, or communication mechanism is specified, matching score 0.
  • eip.md · Specification — Execution layer, lines 33-35 The assigned EIP explicitly requires no execution-layer change.
Uncertainty: Any interface work belonging to the EIP-7002 dependency is not a direct EIP-7251 change.
Transition-tool interface changes0No field or mechanism for the execution state-transition tool interface is introduced, matching score 0.
  • eip.md · Specification — Execution layer, lines 33-35 The proposal says it requires no execution-layer changes.
New invariant on pre-existing testsUnder-specified0The stated effects rework tests of the changed mechanisms; they do not establish a new assertion that pre-existing tests retain their old logic and must additionally check, so score 0 is best supported.
  • eip.md · Specification — Consensus layer change sketch, lines 49-68 The proposal lists changes to existing transition logic and new EIP-specific state and helpers, but does not require tests unrelated to this EIP to assert an additional common output.
Uncertainty: The unspecified BeaconState fields might eventually have implied mechanically added assertions, but this revision does not define them.
New test-framework primitivesUnder-specified0The historical text does not establish a need beyond ordinary protocol test construction, so the existing-primitives score-0 anchor is the best-supported assessment.
  • eip.md · Specification — Consensus layer change sketch, lines 49-68 The sketch identifies protocol containers, state fields, helpers, and modified functions, but specifies no new testing expectations, modifiers, helpers, or framework abstractions.
Uncertainty: Detailed operations for consolidation and custom ceilings are absent, so their eventual test-harness needs cannot be determined.
Cryptography0Changing the weight used by an existing selection lottery does not introduce or modify a cryptographic mechanism itself, so score 0 applies.
  • eip.md · Security Considerations — Aggregator selection, lines 98-100 The existing VRF lottery remains the selection basis; the proposal changes selection to account for validator weight.
Assessment provenance
Assessed EIP revision
ethereum/EIPs@faccff3ac9 EIPS/eip-7251.md committed 2024-01-31 · information cutoff 2024-03-21
Current master · File history · blob 3c63ca90e9 · sha256 15387221cbc1
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-7251.yaml · sha256 3a590fe2c294
Supporting documents in the sealed package
supporting/eip-7002.md
Compare EIP-7251 with other assessmentsAll Prague / Pectra 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.