EIP complexity assessment

EIP-5920: PAY opcode

Assessed in Hegotá. The score describes the EIP text available at the snapshot, not the EIP as it stands today.

ProspectiveHegotáSnapshot 2026-08-25PFI at snapshotLayers: execution

LLM Completescore 16

Human Available in open PRscore 14 · Checklist revision 2· ethspecs/pm #116

Other checklist versions (2)

Merged file · Checklist revision 1 · total 8
Pull request #122 (draft) · Checklist revision 1 · total 8 · same scores as the shown checklist

LLM · Checklist revision 22026-08-26 · Original snapshot · 16 Human · Checklist revision 2Available in open PR · 14 CompareHuman vs LLM · same checklist revision

Evaluated on: 2026-08-26 · Spec revision: 2026-08-25 · ac450a4ab2 · Inclusion status at snapshot: PFI

Scope at the cutoff. Execution-layer-only assessment of the sealed Draft EIP-5920 snapshot. The proposal adds one state-accessing, dynamically priced PAY opcode that moves ether without executing recipient code. The principal test matrix combines gas-boundary ordering with warm/cold, static/non-static, valid/invalid address, existing/nonexistent recipient, zero/nonzero value, sufficient/insufficient balance, success/revert, and direct/delegated recipient cases; independent dimensions multiply rather than merely add.

16MediumMedium

Evaluator: LLMChecklist v2
Confidence: Medium
Under-specified at assessment cutoff: Yes — 1 criterion affected
Plausible range: 15–16 (Medium)
Snapshot: 2026-08-25 · EIP revision ac450a4ab2 (2026-08-25)

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

Edge/boundary conditions3
Added opcodes2
EVM Gas rule changes2
State-access ordering within opcode execution2

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 is materially but narrowly under-specified for zero-value PAY to a nonexistent address: it gives the gas branch and warm-set update but does not normatively state whether account-touch/account-creation bookkeeping occurs or define the account-existence predicate. EIP-7523 strongly constrains the intended result, so this is recorded once under the consensus-ambiguity criterion and is not multiplied across other anchors.

Plausible total

15–16
recorded score 16 · plausible tiers Medium

Affected criteria (1)

Unspecified behavior requiring cross-client consensus (1)

Unresolved questions at the cutoff (2)

Does zero-value PAY to a nonexistent address only warm the address, or also touch or create an account for state-transition bookkeeping?
What exact account-existence predicate governs GAS_NEW_ACCOUNT and recipient creation for PAY on EIP-7523-compatible networks?

Notable ambiguities noted by the assessor (2)

The specification's ordered list places gas charging before warming, but the existence lookup needed to calculate gas necessarily precedes the charge; tests should distinguish lookup, charge, recorded access, and transfer at exact gas boundaries.
PAY to the current address and PAY to a delegated EOA are constructible balance-transfer cases; the general transfer wording implies ordinary balance semantics while expressly excluding recipient code execution.

Criterion breakdown

EIP-5920 Hegotá: LLM criterion scores and rationale
Criterion	Score	Why this score	Evidence / uncertainty
Edge/boundary conditions	3	Multiple edge-prone mechanisms combine, and gas-boundary ordering across the independent access, static, address, existence, value, balance, and outcome dimensions requires an elevated number of cases.	eip.md · Specification > Behavior Defined branches include static exceptional failure, high-byte address failure, sufficient versus insufficient balance, and success status. eip.md · Specification > Gas Cost Gas branches independently on warm/cold address, account existence, and zero/nonzero value. supporting/eip-7523.md · Specification Post-merge empty accounts are prohibited and tests containing them are invalid, creating a network-state boundary for PAY compatibility. Confidence: High Uncertainty: Exact case counts are unavailable because tests are prohibited, but the multiplicative dimensions are explicit in the sealed specifications.
Added opcodes	2	PAY is a single complex opcode because it has nontrivial stack/state behavior and a dynamic gas cost.	eip.md · Abstract; Specification > Behavior; Specification > Gas Cost One opcode, PAY at 0xfc, takes two stack values, performs conditional balance transfer, and has dynamic gas based on state and value. Confidence: High Uncertainty: The dynamic gas schedule independently satisfies the score-2 complexity anchor.
EVM Gas rule changes	2	A new opcode-specific dynamic gas calculation is introduced using existing gas constants and access-list machinery; the proposal does not reprice or rewrite the gas rule of an existing opcode.	eip.md · Specification > Gas Cost PAY has a new dynamic gas schedule summing warm/cold account access, new-account, and nonzero-value charges. supporting/eip-2929.md · Specification > Parameters; Specification > Storage read changes The referenced warm/cold constants and transaction-wide accessed_addresses mechanism supply the account-access component. Confidence: High Uncertainty: The schedule reuses existing mechanisms, but its three-part conditional sum is still a new charging rule, placing it at the score-2 anchor.
State-access ordering within opcode execution	2	PAY is a new state-accessing operation whose ordered gas charge, warm-set update, balance check, and transfer must be tested at each reachable gas boundary. This matches the score-2 new-operation anchor.	eip.md · Specification > Behavior PAY checks static mode, pops and validates inputs, charges gas, warms the address, then conditionally transfers value and pushes success. supporting/eip-2929.md · Specification > Storage read changes EIP-2929 establishes that account-access gas and warming timing are consensus-visible and that reverted scopes restore access sets. Confidence: High Uncertainty: The broad order is explicit. Boundary coverage still multiplies across cold/warm, static/non-static, validity, balance, value, and outcome cases.
Security risks	2	Balance mutation interacts with static-state protection, account/access bookkeeping, and delegated-code expectations. These are a limited set of critical components requiring targeted review and fuzzing, not an extensive redesign across multiple security subsystems.	eip.md · Motivation; Specification > Behavior; Security Considerations PAY changes balances without recipient execution, must reject static execution, returns failure for insufficient balance, and makes forced funding cheaper and easier. supporting/eip-7702.md · Abstract; Backwards Compatibility Delegated EOAs can execute code and spend their balances when called, making PAY's no-code-execution guarantee relevant to delegated accounts. Confidence: Medium Uncertainty: The EIP argues forced funding is already possible, reducing but not removing implementation risk; no prohibited deployment evidence is used.
Cross-EIP interactions	2	Coordinated cases are needed for static failure (214), warm/cold access effects (2929), the empty-account network constraint (7523), and payment to delegated EOAs without code execution (7702). The interactions are explicit but localized and do not require extensive redesign of existing vectors.	eip.md · Front matter requires; Specification > Behavior; Specification > Gas Cost; Motivation EIP-5920 requires 214, 2929, and 7523, and explicitly motivates PAY for delegated EOAs introduced by EIP-7702. supporting/eip-214.md · Specification Static execution makes state-changing operations exceptional. supporting/eip-2929.md · Specification > Storage read changes Warm/cold account charging and accessed-address updates are transaction scoped. supporting/eip-7523.md · Specification Post-merge empty accounts are prohibited and such test cases are invalid. supporting/eip-7702.md · Specification > Delegation indicator; Backwards Compatibility Delegated EOAs execute pointed-to code on calls and can spend balances during execution. Confidence: High Uncertainty: References to EIPs 141, 1153, 1283, 2200, and 6780 are rationale, historical context, or alternative mechanisms and are not counted as coordinated mechanism dependencies. Interacting EIPs: EIP-214, EIP-2929, EIP-7523, EIP-7702
Patterns affecting pre-existing tests	1	The narrow pre-existing category that treats 0xfc as an unavailable or exceptional instruction must be fork-aware; other bytecode behavior is not changed by the proposal.	eip.md · Specification > Behavior; Backwards Compatibility Opcode byte 0xfc becomes PAY and the EIP states that the change requires a hard fork. Confidence: Medium Uncertainty: The package contains no test inventory, so only the mechanically implied opcode-byte regression category is counted.
Performance risks	1	The new mechanism warrants isolated benchmarks for cold/warm and account creation/value-transfer paths, but it is bounded and does not alter performance of executions that do not use PAY.	eip.md · Specification > Behavior; Specification > Gas Cost PAY adds bounded account lookup, access-set update, balance checks, and at most one balance transfer, without recipient execution. Confidence: Medium Uncertainty: No package implementation or benchmark evidence is available or permitted; the score reflects only the specified work.
Unspecified behavior requiring cross-client consensusUnder-specified	1	A small, localized account-lifecycle detail is not stated normatively, but the zero new-account charge and EIP-7523 dependency give it an obvious intended reading. This matches the score-1 anchor.	eip.md · Specification > Behavior; Specification > Gas Cost The text specifies warming and value transfer but does not explicitly say whether zero-value PAY to a nonexistent address performs account-touch or account-creation bookkeeping, nor precisely define the existence predicate. supporting/eip-7523.md · Specification Empty accounts are prohibited post-merge and test cases containing them are invalid, making the missing zero-value/nonexistent-account wording localized and strongly constraining its intended resolution. Confidence: Medium Uncertainty: The package contains no permitted client, devnet, or discussion evidence; the ambiguity is assessed from the sealed specification alone.

Show 19 zero-score criteria

Zero-score criteria (Checklist revision 2)
Criterion	Why this score	Evidence / uncertainty
Modified opcodes	No pre-existing opcode behavior is modified.	eip.md · Specification > Behavior The specification introduces PAY and does not change any existing opcode result or deprecate an opcode. Uncertainty: References to CALL, EXTCALL, and INVALID are comparative or motivational only.
Added precompiles	No precompile is added.	eip.md · Abstract; Specification The proposal adds an opcode and no precompile address or precompile function. Uncertainty: No precompile mechanism appears in the sealed proposal.
Modified precompiles	No existing precompile is modified.	eip.md · Specification PAY performs no recipient code call and specifies no precompile logic or gas change. Uncertainty: A precompile address can receive value like another address, but its precompile behavior is untouched.
Added system contracts	No system contract is added.	eip.md · Abstract; Specification The feature is implemented as an EVM opcode, not a system contract. Uncertainty: No system-contract deployment or address is specified.
Modified system contracts	No pre-existing system contract is directly or indirectly modified.	eip.md · Specification PAY applies generally to EVM execution and names no system contract or special system-contract behavior. Uncertainty: No system-contract interaction appears in the package.
Blob gas accounting changes	No blob gas accounting is introduced or modified.	eip.md · Specification > Gas Cost The complete PAY schedule uses account-access, new-account, and value transfer gas only; it defines no blob gas rule. Uncertainty: No blob-related behavior appears in the sealed proposal.
State gas accounting changes	Although PAY can change balances, the snapshot adds no state-gas accounting site or mechanism as that rubric row defines it.	eip.md · Specification > Gas Cost PAY charges ordinary EVM gas constants and specifies no StateGasCosts, state-byte rate, state-gas budget, reservoir, or spill rule. Uncertainty: No future Hegotá state-gas integration is inferred beyond the sealed text.
New EVM gas refund	No gas-refund mechanism is introduced.	eip.md · Specification > Gas Cost The PAY gas formula contains charges only and specifies no refund. Uncertainty: No refund behavior appears in the sealed proposal.
New transaction types	No new transaction type is introduced.	eip.md · Abstract; Specification PAY is available through EVM bytecode and no transaction envelope or type is added. Uncertainty: No transaction-type surface appears in the sealed proposal.
New or modified transaction validity mechanisms	No transaction validity rule or intrinsic-gas calculation is changed.	eip.md · Specification; Backwards Compatibility The hard-fork change concerns opcode execution and does not alter transaction validity or intrinsic gas. Uncertainty: Exceptional opcode execution is not transaction-envelope validity under this anchor.
New block / header fields	No new block or header field is introduced.	eip.md · Specification The proposal defines no block-body or header field. Uncertainty: No block/header surface appears in the package.
Encoding changes (RLP/SSZ)	No RLP, SSZ, or other interface-level encoding change is introduced.	eip.md · Specification The proposal changes EVM bytecode execution only and defines no transaction, block, or interface encoding. Uncertainty: The opcode byte assignment is not a transaction/block/interface encoding change under this anchor.
Block syncing changes	No block-RLP syncing mechanism is introduced.	eip.md · Specification PAY changes opcode execution and defines no block RLP field or validation rule. Uncertainty: No syncing surface appears in the sealed proposal.
New fork activation mechanism	No fork-block migration or modification is introduced.	eip.md · Backwards Compatibility; Specification The proposal requires a hard fork but specifies only post-activation opcode behavior, with no activation-block state or internal-variable mutation. Uncertainty: Activation of a new opcode rule alone does not satisfy this anchor.
Engine API changes	No Engine API change is introduced.	eip.md · Specification The proposal contains no Engine API endpoint, field, or communication rule. Uncertainty: No Engine API surface appears in the sealed proposal.
Transition-tool interface changes	Existing transition-tool inputs and outputs are sufficient.	eip.md · Specification The specification changes EVM opcode execution and introduces no external transition-tool field or mode. Uncertainty: The hard-fork requirement alone is not a new transition-tool interface.
New invariant on pre-existing tests	Tests not exercising PAY gain no new value or artifact that they must additionally assert.	eip.md · Specification All new outputs and state effects are conditional on executing PAY; no block-wide or transaction-wide output is added for unrelated executions. Uncertainty: Fork-aware invalid-opcode reworking is scored in the preceding row, not duplicated here as a new invariant.
New test-framework primitives	These outcomes can be expressed with existing opcode/state/gas expectations; no new framework abstraction is required by the text.	eip.md · Specification > Behavior; Specification > Gas Cost PAY produces ordinary EVM stack, gas, access-set, balance, success, and exceptional-halt outcomes. Uncertainty: Framework implementations and tests are prohibited and absent, so the score is limited to requirements evident from the specification.
Cryptography	No cryptographic mechanism is introduced or changed.	eip.md · Abstract; Specification PAY validates an address, charges gas, and transfers ether without adding or modifying any cryptographic operation. Uncertainty: No cryptography-related behavior appears in the package.

Assessment provenance

Assessed EIP revision: ethereum/EIPs@ac450a4ab2 EIPS/eip-5920.md committed 2026-08-25 · information cutoff 2026-08-25T11:56:58Z
Current master · File history · blob f8c6f353cb · sha256 f9b6d2938174
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/08-hegota-prospective-complexity-assessment/outputs/assessments/hegota-pfi-2026-08-26/eip-5920.yaml · sha256 8f536805b310
Supporting documents in the sealed package: supporting/eip-141.md, supporting/eip-214.md, supporting/eip-1153.md, supporting/eip-1283.md, supporting/eip-2200.md, supporting/eip-2929.md, supporting/eip-6780.md, supporting/eip-7523.md, supporting/eip-7702.md

Evaluated on: Not recorded

14MediumMedium

Evaluator: HumanChecklist v2
Confidence: Not recorded
Under-specified at assessment cutoff: Not recorded in the checklist
Checklist published: 2026-08-18
Source: open ethspecs/pm pull request #116

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 Human total. Hover or focus a segment for its score and rationale.

Top complexity drivers

Added opcodes2
State-access ordering within opcode execution2
State gas accounting changes2
Security risks2

Criterion breakdown

EIP-5920 Hegotá: Human criterion scores and rationale
Criterion	Score	Why this score	Notes
Added opcodes	2	One new complex opcode: `PAY` (`0xfc`), complex via its dynamic gas cost. Was 3 under revision 1; level 3 requires multiple opcodes.	—
State-access ordering within opcode execution	2	New state-accessing operation whose order must be settled. PAY's gas depends on whether `addr` exists, read before the transfer is known to succeed. Unspecified: whether `addr` enters the BAL when PAY returns 0 for insufficient balance, and whether `GAS_NEW_ACCOUNT` is still charged for an account never created.	—
State gas accounting changes	2	New state-gas charging site. PAY creates an account when `addr` is absent and `val` non-zero, costing `StateGasCosts.NEW_ACCOUNT` (183,600 state gas) plus `ACCOUNT_WRITE` (9,000 execution gas). The EIP's gas table has no state-gas term, so this branch is unpriced.	—
Security risks	2	Force-funding without calling is already possible via `SELFDESTRUCT` and coinbase priority fees, so no invariant is newly broken, but `PAY` makes it much cheaper.	—
Edge/boundary conditions	2	Multiple boundary-prone mechanisms, none needing elevated cases: `val` 0, zero-address, `addr` equal to self, the two exceptional halts (high 12 bytes set, static frame), and the gas tree over warm/cold, `addr` exists or not, and `val` zero or not. All within one opcode, so 2 rather than the revision-1 score of 3.	—
Cross-EIP interactions	2	Five interacting EIPs, each individually simple: EIP-7523 (hard precondition — PAY "cannot be implemented on networks with empty accounts"), EIP-7708 (should emit a transfer log), EIP-7928 (BAL entries), EIP-8037 (state gas), EIP-6780 (cited as the existing force-send route). Was 0 under revision 1.	—
Unspecified behavior requiring cross-client consensus	2	Predates three live Amsterdam mechanisms and requires an update: whether `PAY` emits an EIP-7708 transfer log, how its accesses and balance changes enter the EIP-7928 BAL, and how account creation is priced under EIP-8037. Self-directed PAY (`addr` equal to the current address) is also unstated.	—

Show 21 zero-score criteria

Zero-score criteria (Checklist revision 2)
Criterion	Why this score	Notes
Modified opcodes	No rationale recorded.	—
Added precompiles	No rationale recorded.	—
Modified precompiles	No rationale recorded.	—
Added system contracts	No rationale recorded.	—
Modified system contracts	No rationale recorded.	—
EVM Gas rule changes	No new mechanism. PAY composes existing ones: warm/cold access, `GAS_NEW_ACCOUNT`, `GAS_CALL_VALUE`. Its dynamic cost is scored under Added opcodes.	—
Blob gas accounting changes	No rationale recorded.	—
New EVM gas refund	No rationale recorded.	—
New transaction types	No rationale recorded.	—
New or modified transaction validity mechanisms	No rationale recorded.	—
New block / header fields	No rationale recorded.	—
Encoding changes (RLP/SSZ)	No rationale recorded.	—
Block syncing changes	No rationale recorded.	—
New fork activation mechanism	No rationale recorded.	—
Engine API changes	No rationale recorded.	—
Transition-tool interface changes	No rationale recorded.	—
Patterns affecting pre-existing tests	Purely additive; no existing test changes.	—
New invariant on pre-existing tests	No rationale recorded.	—
New test-framework primitives	Existing primitives suffice: balance expectations and BAL balance-change primitives already exist.	—
Performance risks	No rationale recorded.	—
Cryptography	No rationale recorded.	—

Assessment provenance

Rubric: Checklist revision 2 · ethspecs/pm@3d8c0128c5
Evaluator: STEEL team · ethspecs/pm complexity_assessments
Source record: Open pull request #116: Update EIP-5920 complexity assessment to checklist revision 2 · checklist at c2b40ca1b8 · updated 2026-08-18
blob ff44f79881 · sha256 6f9c855fe336
Research record: research/tasks/09-hegota-human-assessment-snapshot/outputs/assessments/eip-5920.yaml · sha256 133e9319f25b

Both assessments applied Checklist revision 2 (28 criteria) to EIP-5920 in Hegotá. Δ is LLM minus Human.

Using the latest scored LLM evaluation for this checklist: 2026-08-26 · spec 2026-08-25 · ac450a4ab2. The Human and LLM assessments may use different spec revisions.

LLM16Medium

Human14Medium

Δ total+2Same tier

Criteria22/28agree exactly · 4 differ by 1 · 2 differ by 2+

Complexity profiles side by side

LLM

Human

Largest disagreements: EVM Gas rule changes (+2), State gas accounting changes (−2), Patterns affecting pre-existing tests (+1), Edge/boundary conditions (+1), Performance risks (+1)

Show differences only (6 criteria)

Per-criterion scores, Human versus LLM, ordered by the size of the difference
Criterion	LLM	Human	Δ	Agreement	Rationale from each source
EVM Gas rule changes	2	0	+2	Differ by 2+	Show rationale LLM A new opcode-specific dynamic gas calculation is introduced using existing gas constants and access-list machinery; the proposal does not reprice or rewrite the gas rule of an existing opcode. Human No new mechanism. PAY composes existing ones: warm/cold access, `GAS_NEW_ACCOUNT`, `GAS_CALL_VALUE`. Its dynamic cost is scored under Added opcodes.
State gas accounting changes	0	2	−2	Differ by 2+	Show rationale LLM Although PAY can change balances, the snapshot adds no state-gas accounting site or mechanism as that rubric row defines it. Human New state-gas charging site. PAY creates an account when `addr` is absent and `val` non-zero, costing `StateGasCosts.NEW_ACCOUNT` (183,600 state gas) plus `ACCOUNT_WRITE` (9,000 execution gas). The EIP's gas table has no state-gas term, so this branch is unpriced.
Patterns affecting pre-existing tests	1	0	+1	Differ by 1	Show rationale LLM The narrow pre-existing category that treats 0xfc as an unavailable or exceptional instruction must be fork-aware; other bytecode behavior is not changed by the proposal. Human Purely additive; no existing test changes.
Performance risks	1	0	+1	Differ by 1	Show rationale LLM The new mechanism warrants isolated benchmarks for cold/warm and account creation/value-transfer paths, but it is bounded and does not alter performance of executions that do not use PAY. Human No rationale recorded.
Edge/boundary conditions	3	2	+1	Differ by 1	Show rationale LLM Multiple edge-prone mechanisms combine, and gas-boundary ordering across the independent access, static, address, existence, value, balance, and outcome dimensions requires an elevated number of cases. Human Multiple boundary-prone mechanisms, none needing elevated cases: `val` 0, zero-address, `addr` equal to self, the two exceptional halts (high 12 bytes set, static frame), and the gas tree over warm/cold, `addr` exists or not, and `val` zero or not. All within one opcode, so 2 rather than the revision-1 score of 3.
Unspecified behavior requiring cross-client consensus	1	2	−1	Differ by 1	Show rationale LLM A small, localized account-lifecycle detail is not stated normatively, but the zero new-account charge and EIP-7523 dependency give it an obvious intended reading. This matches the score-1 anchor. Human Predates three live Amsterdam mechanisms and requires an update: whether `PAY` emits an EIP-7708 transfer log, how its accesses and balance changes enter the EIP-7928 BAL, and how account creation is priced under EIP-8037. Self-directed PAY (`addr` equal to the current address) is also unstated.
Added opcodes	2	2	0	Agree	Show rationale LLM PAY is a single complex opcode because it has nontrivial stack/state behavior and a dynamic gas cost. Human One new complex opcode: `PAY` (`0xfc`), complex via its dynamic gas cost. Was 3 under revision 1; level 3 requires multiple opcodes.
Modified opcodes	0	0	0	Agree	Show rationale LLM No pre-existing opcode behavior is modified. Human No rationale recorded.
Added precompiles	0	0	0	Agree	Show rationale LLM No precompile is added. Human No rationale recorded.
Modified precompiles	0	0	0	Agree	Show rationale LLM No existing precompile is modified. Human No rationale recorded.
Added system contracts	0	0	0	Agree	Show rationale LLM No system contract is added. Human No rationale recorded.
Modified system contracts	0	0	0	Agree	Show rationale LLM No pre-existing system contract is directly or indirectly modified. Human No rationale recorded.
State-access ordering within opcode execution	2	2	0	Agree	Show rationale LLM PAY is a new state-accessing operation whose ordered gas charge, warm-set update, balance check, and transfer must be tested at each reachable gas boundary. This matches the score-2 new-operation anchor. Human New state-accessing operation whose order must be settled. PAY's gas depends on whether `addr` exists, read before the transfer is known to succeed. Unspecified: whether `addr` enters the BAL when PAY returns 0 for insufficient balance, and whether `GAS_NEW_ACCOUNT` is still charged for an account never created.
Blob gas accounting changes	0	0	0	Agree	Show rationale LLM No blob gas accounting is introduced or modified. Human No rationale recorded.
New EVM gas refund	0	0	0	Agree	Show rationale LLM No gas-refund mechanism is introduced. Human No rationale recorded.
New transaction types	0	0	0	Agree	Show rationale LLM No new transaction type is introduced. Human No rationale recorded.
New or modified transaction validity mechanisms	0	0	0	Agree	Show rationale LLM No transaction validity rule or intrinsic-gas calculation is changed. Human No rationale recorded.
New block / header fields	0	0	0	Agree	Show rationale LLM No new block or header field is introduced. Human No rationale recorded.
Encoding changes (RLP/SSZ)	0	0	0	Agree	Show rationale LLM No RLP, SSZ, or other interface-level encoding change is introduced. Human No rationale recorded.
Block syncing changes	0	0	0	Agree	Show rationale LLM No block-RLP syncing mechanism is introduced. Human No rationale recorded.
New fork activation mechanism	0	0	0	Agree	Show rationale LLM No fork-block migration or modification is introduced. Human No rationale recorded.
Engine API changes	0	0	0	Agree	Show rationale LLM No Engine API change is introduced. Human No rationale recorded.
Transition-tool interface changes	0	0	0	Agree	Show rationale LLM Existing transition-tool inputs and outputs are sufficient. Human No rationale recorded.
New invariant on pre-existing tests	0	0	0	Agree	Show rationale LLM Tests not exercising PAY gain no new value or artifact that they must additionally assert. Human No rationale recorded.
New test-framework primitives	0	0	0	Agree	Show rationale LLM These outcomes can be expressed with existing opcode/state/gas expectations; no new framework abstraction is required by the text. Human Existing primitives suffice: balance expectations and BAL balance-change primitives already exist.
Security risks	2	2	0	Agree	Show rationale LLM Balance mutation interacts with static-state protection, account/access bookkeeping, and delegated-code expectations. These are a limited set of critical components requiring targeted review and fuzzing, not an extensive redesign across multiple security subsystems. Human Force-funding without calling is already possible via `SELFDESTRUCT` and coinbase priority fees, so no invariant is newly broken, but `PAY` makes it much cheaper.
Cryptography	0	0	0	Agree	Show rationale LLM No cryptographic mechanism is introduced or changed. Human No rationale recorded.
Cross-EIP interactions	2	2	0	Agree	Show rationale LLM Coordinated cases are needed for static failure (214), warm/cold access effects (2929), the empty-account network constraint (7523), and payment to delegated EOAs without code execution (7702). The interactions are explicit but localized and do not require extensive redesign of existing vectors. Human Five interacting EIPs, each individually simple: EIP-7523 (hard precondition — PAY "cannot be implemented on networks with empty accounts"), EIP-7708 (should emit a transfer log), EIP-7928 (BAL entries), EIP-8037 (state gas), EIP-6780 (cited as the existing force-send route). Was 0 under revision 1.

Compare EIP-5920 with other assessments All Hegotá 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.

OP+
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.
PC+
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.
ORD
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.
SGAS
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.
ENC
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.
ACT
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).
T8N
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.).
INV
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.

XEIP
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.
UNSP
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.