EIP complexity assessment

EIP-8182: Private ETH and ERC-20 Transfers

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 20

Human Pending· No STEEL checklist existed on the ethspecs/pm default branch or in any open pull request at the snapshot.

LLM assessment

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 EIP-8182 snapshot: the fork-installed shielded-pool system contract, its state and call paths, the Groth16/Poseidon2 pool-proof and auth-policy mechanisms, ETH/ERC-20 asset movement, and activation behavior. Wallet, mempool, note-delivery, and network-anonymity infrastructure identified as out of scope by the EIP is excluded.

20MediumMedium

Evaluator: LLMChecklist v2
Confidence: Medium
Under-specified at assessment cutoff: Yes — 3 criteria affected
Plausible range: 19–22 (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.

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 activation artifact is not reproducible from the sealed evidence: the exact system-contract bytecode and Groth16 verification key await a trusted setup, the exact pool-circuit artifact is not included, and the referenced Poseidon parameter/vector assets are outside the assessment source list. This chiefly limits cryptographic vectors, performance baselines, and final cross-client artifact agreement without changing the clearly specified count of protocol surfaces.

Plausible total

19–22
recorded score 20 · plausible tiers Medium

Affected criteria (3)

Performance risks (2)
Cryptography (3)
Unspecified behavior requiring cross-client consensus (2)

Unresolved questions at the cutoff (4)

What exact system-contract bytecode and initial account state will all clients install at activation?
What finalized Groth16 circuit artifact, verification key, and trusted-setup transcript determine the embedded verifier?
Do the referenced Poseidon2 constants and vectors fully determine and test every sponge and Merkle-tree context described by the prose?
What measured execution and state-growth costs follow from the finalized bytecode, proof verifier, auth-verifier calls, and allowed payload sizes?

Notable ambiguities noted by the assessor (3)

Same-block auth-policy roots are intentionally not retained after later same-block mutations, so transaction ordering determines whether an intermediate root remains usable; the EIP recommends waiting a block but does not make that wallet behavior mandatory.
ERC-20 compatibility is deliberately narrower than the nominal interface: fee-on-transfer and rebasing behavior can fail or under-deliver, and the supporting EIP-20 snapshot contains no normative body for comparison.
Auth verifier proof formats and verification-key derivation are delegated to companion standards, while the pool contract accepts any user-registered verifier satisfying only the staticcall envelope.

Criterion breakdown

EIP-8182 Hegotá: LLM criterion scores and rationale
Criterion	Score	Why this score	Evidence / uncertainty
New fork activation mechanism	3	Installing code and an account as part of the activation state transition is a fork-block state modification, matching the score-3 anchor.	eip.md · Section 5.1, Deployment and Upgrade Model At activation, clients must install a system-contract account with exact code at the fixed shielded-pool address, and its storage persists across later fork replacements. Confidence: High Uncertainty: The exact bytecode is not yet pinned, but the required activation-time state modification is unambiguous.
Security risks	3	The mechanism touches multiple critical components and custody invariants; an implementation error can compromise pool funds or authorization while other errors can cause replay, lockout, leakage, or denial of service. It requires extensive security review and fuzzing.	eip.md · Section 4, Architecture; Security Considerations The pool circuit is the all-funds security boundary; the design also relies on a trusted setup, custom commitments/nullifiers, root histories, replay protection, user-selected auth verifiers, and exact asset-transfer handling. eip.md · Sections 5.4 and 8, execution and circuit requirements Security-critical checks span proof canonicality, field/address ranges, nullifier and intent uniqueness, cross-proof binding, value conservation, token consistency, authorization, external calls, and reentrancy. Confidence: High Uncertainty: Risk is scoped to the execution-layer pool and its users as the EIP states; consensus-layer and out-of-scope network privacy are not scored.
Edge/boundary conditions	3	There are many independent boundary-prone mechanisms, and root aging, replay/expiry, output locking, token-call return shapes, and real/phantom or dummy combinations each require elevated case matrices.	eip.md · Sections 5.2.1, 5.4, 8.2, 8.5, 8.10; Test Cases The EIP defines block- and count-based root-history edges, two tree capacity boundaries, field/address/amount ranges, proof encodings, transfer/withdrawal branches, real/phantom inputs, real/dummy outputs, expiry, replay, rotation, and output-lock combinations. Confidence: High Uncertainty: Exact circuit and bytecode artifacts may reveal further edges; score 3 already matches the highest defined non-exceptional anchor.
CryptographyUnder-specified	3	Multiple mechanisms are introduced, including a custom Poseidon2 sponge construction and a compound Groth16/auth-proof protocol with commitments, nullifiers, and Merkle membership. At least the composed relation and cross-proof binding are proposal-specific and demand dedicated vectors and adversarial testing.	eip.md · Sections 3.3-3.4, Poseidon Hash and Merkle Tree Constructions The EIP fixes a custom length-tagged Poseidon2 BN254 sponge and three Merkle-tree constructions with domain-separated commitment formulas. eip.md · Sections 4, 5.5, and 8.1, split proofs and verification A fork-managed Groth16 proof, permissionless auth proofs, embedded verification key, and two-value cross-proof coupling jointly enforce the spend relation. Confidence: High Uncertainty: The referenced Poseidon parameter/vector assets and finalized verification key are not available as scoring evidence, limiting artifact-level review without reducing the evident mechanism count.
Added system contracts	2	The proposal adds a single stateful system contract, exactly matching score 2.	eip.md · Sections 1 and 5.1-5.3, system-contract definition and state One shielded-pool system contract is installed at a protocol-defined address and maintains commitment trees, histories, nullifiers, replay IDs, identity entries, and an auth-policy registry. Confidence: High Uncertainty: Its exact bytecode is pending, but its count and statefulness are explicit.
Performance risksUnder-specified	2	Core proof and tree operations can be benchmarked directly, but cumulative state growth, arbitrary auth-verifier code, ERC-20 behavior, payload sizes, and root-history throughput prevent complete isolation. The EIP adds a new path rather than broadly changing existing execution benchmarks, fitting score 2.	eip.md · Sections 5.2, 5.4, and 5.5; Security Considerations, State Growth Each spend combines Groth16 verification over 19 public inputs, auth-verifier staticcall, multiple state-set writes, three tree insertions, payload hashing, and optional external asset transfer; pool state is append-only and not safely prunable. eip.md · Rationale, Groth16 BN254 Pool Proof System Verification gas is dominated by 19 scalar multiplications and a final pairing. Confidence: Medium Uncertainty: Final bytecode, verification key, and concrete circuit artifacts are pending, so exact execution cost and benchmark coverage are not baselinable.
Cross-EIP interactions	2	The pool depends on EIP-20 behavior and needs coordinated token-path tests, including nonstandard return shapes and explicitly incompatible fee or rebasing behavior, but the interaction is confined to asset ingress and egress. EIP-4844 is only a trusted-setup analogy in the EIP text and does not require coordinated EIP-4844 test cases.	eip.md · Front matter requires; Sections 5.4.1-5.4.2, ERC-20 call semantics EIP-8182 explicitly requires EIP-20 and defines deposit/withdrawal integration through balanceOf, transferFrom, and transfer, including strict return-data and balance-delta handling. supporting/eip-20.md · Front matter and body The sealed supporting snapshot identifies EIP-20 as the ERC dependency but contains only a move notice and no additional normative interface text. Confidence: High Uncertainty: The EIP-20 support file lacks its normative body, but EIP-8182 itself states the integration behavior needed for this complexity classification. Interacting EIPs: EIP-20
Unspecified behavior requiring cross-client consensusUnder-specified	2	Clients need coordinated agreement on the exact activation code, verification key, and circuit-derived artifacts before bytecode- and proof-level vectors can be baselined. The gaps are material but localized to the new pool artifact, fitting score 2 rather than re-baselining a newly observable pre-existing behavior.	eip.md · Section 5.1 and 5.5, deployment and pool-proof verification The exact system-contract bytecode and embedded verification key are not pinned; bytecode is to be finalized after a future trusted-setup ceremony. eip.md · Sections 3.3 and 8, Poseidon assets and circuit requirements Hash constants/vectors are delegated to referenced assets, while the pool circuit is specified as requirements rather than a sealed circuit/VK artifact in this package. Confidence: Medium Uncertainty: The prose fixes many observable cases and provides extensive test requirements, so the remaining uncertainty is narrower than the overall feature surface but blocks an authoritative artifact-level baseline.

Show 20 zero-score criteria

Zero-score criteria (Checklist revision 2)
Criterion	Why this score	Evidence / uncertainty
Added opcodes	No opcode is added.	eip.md · Abstract The EIP explicitly states that it introduces no new opcode. Uncertainty: No ambiguity is present.
Modified opcodes	No pre-existing opcode behavior is modified or deprecated.	eip.md · Abstract; Backwards Compatibility The proposal confines the protocol change to the system contract and does not change existing contract semantics. Uncertainty: No ambiguity is present.
Added precompiles	No precompile is added.	eip.md · Abstract; Rationale, Groth16 BN254 Pool Proof System The EIP explicitly adds no precompile; its verifier uses existing ECADD/ECMUL/ECPAIRING calls. Uncertainty: Use of existing precompiles is an integration dependency, not an added precompile.
Modified precompiles	No pre-existing precompile is modified.	eip.md · Abstract; Sections 5.5 and Rationale, Groth16 BN254 Pool Proof System Existing elliptic-curve precompiles are called by the verifier, with no behavioral or gas-schedule modification specified. Uncertainty: No modification is implied by ordinary calls to them.
Modified system contracts	No pre-existing system contract is modified by this proposal.	eip.md · Abstract; Section 5.1, Deployment and Upgrade Model The EIP installs a new account and describes only possible future hard-fork replacement of that account's code. Uncertainty: A future replacement is not part of the assessed activation change.
EVM Gas rule changes	Contract calls and proof verification consume existing EVM gas, but no gas schedule or accounting mechanism is created or changed.	eip.md · Abstract; Section 5, System Contract The EIP limits its protocol change to installing a system contract and specifies ordinary contract execution without a new EVM gas-accounting rule. Uncertainty: Exact system-contract bytecode is pending, but that does not by itself specify a change to EVM gas accounting.
State-access ordering within opcode execution	No opcode's state-access position or gas-charge ordering is changed.	eip.md · Abstract; Backwards Compatibility The EIP introduces no opcode and says it does not modify existing contract semantics. Uncertainty: The system contract performs state accesses as ordinary contract code; none is an opcode-ordering rule.
Blob gas accounting changes	No blob gas accounting is introduced or modified.	eip.md · Abstract; Section 5, System Contract The specified change is a shielded-pool system contract and contains no blob-gas rule. Uncertainty: EIP-4844 is cited only as an analogy for a setup ceremony, not as an accounting dependency.
State gas accounting changes	New ordinary storage writes are not a change to the rubric's state-gas accounting mechanism.	eip.md · Sections 5.2 and 5.4, State and Execution The pool writes contract storage for trees, nullifiers, replay IDs, and policies, but the EIP specifies no state-gas budget, rate, charging site, or spill rule. Uncertainty: Storage volume is considered under performance and security, not counted again as state-gas accounting.
New EVM gas refund	No new EVM gas-refund mechanism is introduced.	eip.md · Sections 5.4.1 and 5.4.2, transact and deposit The execution procedures define validation, storage, proof checks, and transfers without any gas-refund behavior. Uncertainty: No refund-related specification gap is visible.
New transaction types	No new transaction type is introduced.	eip.md · Abstract The EIP explicitly states that it introduces no transaction type. Uncertainty: No ambiguity is present.
New or modified transaction validity mechanisms	Contract-level call validation is not a transaction validity mechanism under this anchor.	eip.md · Abstract; Section 5.4, Execution The proposal adds revert conditions inside calls to the pool contract but no validity or intrinsic-gas rule for existing transaction types. Uncertainty: No transaction-envelope change is specified.
New block / header fields	No new block or header field is introduced.	eip.md · Abstract; Section 5, System Contract All new persistent data resides in the system contract; no block or header field is defined. Uncertainty: No ambiguity is present.
Encoding changes (RLP/SSZ)	Contract calldata and proof payload formats do not change the rubric's transaction/block/interface encodings.	eip.md · Abstract; Sections 5.3 and 5.5 The EIP defines Solidity ABI calls and a pool-proof byte string but no transaction, block, RLP/SSZ, or protocol-interface encoding transition. Uncertainty: No Engine API or block encoding is specified.
Block syncing changes	No new block-RLP syncing validation mechanism is specified.	eip.md · Abstract; Sections 5.1 and 5.4 The execution-layer change is an installed account and contract-call behavior; no block RLP validation rule is introduced. Uncertainty: Syncing must reproduce the fork state transition, but that is distinct from this anchor's block-RLP validation mechanism.
Engine API changes	No Engine API change is introduced.	eip.md · Abstract; Section 5, System Contract The EIP specifies a system-contract interface and no Engine API field, endpoint, or communication mechanism. Uncertainty: No Engine API ambiguity is visible in the sealed text.
Transition-tool interface changes	Activation-block behavior changes, but no transition-tool interface field or interface mechanism is specified.	eip.md · Section 5.1, Deployment and Upgrade Model Clients install a fixed-address account at the activation fork, but the EIP defines no new transition-tool input or output field. Uncertainty: A transition tool must distinguish activation from later blocks; the package does not establish that this requires an interface extension rather than existing fork selection.
Patterns affecting pre-existing tests	The snapshot provides no rule requiring pre-existing tests to be reworked; feature and activation tests are new EIP-specific coverage.	eip.md · Abstract; Backwards Compatibility Apart from the new system-contract installation, the EIP disclaims other protocol changes and says existing contracts and ERC-20 interfaces retain their semantics. Uncertainty: A contrived pre-existing test that assumes the fixed system address is empty could be affected, but the package gives no evidence of such a test population.
New invariant on pre-existing tests	Tests unrelated to EIP-8182 are not specified to gain a new assertion.	eip.md · Test Cases; Backwards Compatibility The listed assertions concern EIP-8182 calls and state, while the EIP states that existing contract semantics are unchanged. Uncertainty: Fork-activation allocation tests are about this EIP and therefore do not constitute a new invariant on unrelated tests.
New test-framework primitives	The sealed text does not demonstrate that existing test primitives are insufficient, even though EIP-specific proof fixtures and helpers will be substantial.	eip.md · Test Cases Required cases are expressed as calls, proofs, input ranges, state transitions, reverts, and boundary checks; the EIP does not require a new expectation or modifier abstraction. Uncertainty: The package contains no test-framework inventory, so framework-specific helper needs cannot be established from the snapshot.

Assessment provenance

Assessed EIP revision: ethereum/EIPs@ac450a4ab2 EIPS/eip-8182.md committed 2026-08-25 · information cutoff 2026-08-25T11:56:58Z
Current master · File history · blob 44856f004a · sha256 5fcacb0f71be
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-8182.yaml · sha256 f24a8e332688
Supporting documents in the sealed package: supporting/eip-20.md, supporting/eip-4844.md

Compare EIP-8182 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.