About and feature status
CryptoAPIs is a browser-only developer workbench for EVM JSON-RPC payloads. It is not a hosted API, has no network mode, and holds no wallets or keys.
Your local data
Drafts autosave to this browser's IndexedDB. They are not a cloud backup and can be evicted by the browser. Export a project file to keep a copy.
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Capability status
Each row maps to a requirement ID in the product specification. Classes: L local deterministic, D installed reference data, N network-dependent, X excluded; R1–R3 are release phases.
| ID | Capability | Status | Where / notes |
|---|---|---|---|
| CAP-001 R1/D | Protocol/chain profiles | Done | /api-contracts#profiles, profile picker Ten EVM profiles in a dated, self-authored pack. Bitcoin listed as UNSUPPORTED. |
| CAP-002 R1/L | JSON-RPC request builder | Done | /rpc-builder Method catalogue, per-parameter validation, id/notification checks. No send. |
| CAP-003 R1/L | Batch request inspection | Done | /rpc-builder#batch Matched by id in a Web Worker; duplicates, missing, unexpected, null-id and order findings. |
| CAP-004 R1/L | Response/error explorer | Done | /rpc-builder#explore Transport, incomplete, envelope, RPC error and result layers; revert decoding. |
| CAP-005 R1/L | Hex/data/quantity utilities | Done | /unit-converter#hex QUANTITY vs DATA rules, two's complement, UTF-8. |
| CAP-006 R1/L | Exact integer/unit conversion | Done | /unit-converter BigInt only; refuses to round. |
| CAP-007 R1/L | Address syntax/checksum | Partial | /address-checker EIP-55 done. EIP-1191 chain-specific checksums not implemented. |
| CAP-008 R1/L | ABI encoder/decoder | Done | /abi-decoder Tuples, nested arrays, offset/length bounds, allocation limits. Differentially tested against viem. Fixed-point types UNSUPPORTED. |
| CAP-009 R1/L | Selector/topic tools | Done | /abi-decoder#selectors Keccak-256 via @noble/hashes; collision disclosure; SHA3-256 contrast. |
| CAP-010 R1/L | Calldata inspector | Done | /abi-decoder, home Byte spans, ABI provenance field, labelled guesses when no ABI. |
| CAP-011 R1/L | Event-log decoder | Done | /abi-decoder#logs Indexed/non-indexed separation, topic counts, hashed dynamic indexed values. Worker; CSV/JSONL export. |
| CAP-012 R1/L | Block/tx/receipt viewer | Done | /response-diff#snapshot Snapshot label and provenance; no finality inference. |
| CAP-013 R1/L | Gas/fee calculator | Done | /unit-converter#fees Legacy, EIP-1559 and blob fees on typed inputs. L2 data fees not modelled. |
| CAP-014 R1/L | Timestamp/block interval tools | Done | /unit-converter#time Unit detection, UTC conversion, interpolation from two supplied blocks. |
| CAP-015 R1/L | JSON schema validation | Partial | /api-contracts Common subset with exact integers; unsupported keywords listed, local $ref only. |
| CAP-016 R1/L | Provider response comparison | Done | /response-diff Block/chain context first; missing/null/zero/empty distinct; opt-in normalisation. |
| CAP-017 R1/L | Redaction workbench | Done | /redact Pattern detection, selective redaction, canary verification, memory-only. |
| CAP-018 R1/L | Code snippet generation | Done | /rpc-builder#snippets cURL, fetch, Python, Go, viem 2.x, ethers 6.x with env-var endpoints. |
| CAP-019 R1/L | cURL/OpenAPI/collection import | Partial | /rpc-builder#import, /api-contracts#import cURL, Postman, OpenAPI 3/Swagger 2, OpenRPC as inert data. YAML not supported. |
| CAP-020 R1/L | Fixture library | Done | /mock-scenarios Synthetic success, error, revert, rate-limit, truncated, reorg, batch and snapshot fixtures. |
| CAP-021 R1/L | Local mock scenario runner | Done | /mock-scenarios#runner Seeded, virtual clock, SHA-256 transcript digest. |
| CAP-022 R1/L | Export project/report | Done | /about#project, per-tool exports Project bundle with checksum and pack versions; decode/diff/redaction reports. |
| CAP-023 R2/L | Contract drift/diff | Partial | /response-diff Structural diff only; no per-provider mapping files. |
| CAP-024 R2/L | Pagination/backoff simulation | Partial | /mock-scenarios#runner Backoff, Retry-After and range-cap simulation. No cursor pagination. |
| CAP-025 R2/L | Reorg/finality scenarios | Partial | fixtures, mock runner Reorg fixtures and simulated reorgs; no finality model. |
| CAP-026 R2/L | Token decimal normalisation | Done | /unit-converter#tokens Decimals required, recorded as supplied/unverified. |
| CAP-027 R2/L | Signature verification | Not done | Roadmap. No key import or signing will be added. |
| CAP-028 R2/L | Bitcoin transaction decode | Not done | UNSUPPORTED. Needs an independent codec. |
| CAP-029 R2/L | Local API workflow recipes | Partial | /api-contracts Declarative assertions only. |
| CAP-030 R2/L | CSV/JSONL export | Partial | /abi-decoder#logs Decoded logs with exact string values. |
| CAP-031 R2/D | Protocol learning packs | Partial | route guides Explanatory content per tool; no separate lesson packs. |
| CAP-032 R3/N | Direct read-only provider mode | Not done | Deliberately absent. Network mode is off and has no switch. |
| CAP-033 X | Hosted API gateway/webhooks | Excluded | Needs server infrastructure. |
| CAP-034 X | Broadcast/custody/trading | Excluded | Out of scope. No wallet integration. |
| CAP-101 R2/L | ABI compatibility comparison | Not done | Roadmap. |
| CAP-102 R2/L | RPC error taxonomy | Partial | /rpc-builder#explore Built-in mapping; no user-defined categories. |
| CAP-103 R2/L | Block-tag scenario inspector | Partial | /rpc-builder Per-profile tag explanations in the builder. |
| CAP-106 R2/L | Idempotency/retry simulation | Done | /mock-scenarios#runner Stateful methods never blindly retried. |
| CAP-109 R2/L | Provider schema contract packs | Partial | /api-contracts Standard result schemas, versioned; no provider deviations yet. |
| CAP-111 R3/L | Transaction envelope inspection | Partial | /response-diff#snapshot Type labels for JSON tx objects; raw RLP envelopes not decoded. |
| CAP-115 R3/L | Network/profile mismatch checks | Partial | /rpc-builder#explore eth_chainId vs selected profile. |
Reference data shipped with the site
All packs are self-authored, dated and versioned. None is fetched at runtime and none claims to describe a live network.
cryptoapis.eth-jsonrpc v1.0.0 (2026-10-30). Standard eth_/net_/web3_ read methods, plus signing/broadcast/wallet methods listed as excluded so they are visibly out of scope. Self-authored from the Ethereum execution-apis specification and ethereum.org JSON-RPC docs. Not tested against a live node.
cryptoapis.evm-profiles v1.0.0 (2026-10-30). Ten widely used EVM networks. Bitcoin and non-EVM chains are not included (roadmap). Self-authored from public chain-ID registrations (EIP-155) and client documentation. Not verified against a live node.
cryptoapis.signatures v1.0.0 (2026-10-30). ERC-20, ERC-721, ERC-1155, WETH, Multicall3, ERC-4626, Permit2-style approvals and standard errors (~70 entries). Not a full signature database. Self-authored from the public EIP texts; selectors computed locally.
cryptoapis.fixtures v1.0.0 (2026-10-30). Success, RPC error, revert, transport error, rate limit, truncated, reorg, batch and snapshot cases for the EVM JSON-RPC profile. Synthetic, self-authored. Not collected from any network.
cryptoapis.result-schemas v1.0.0 (2026-10-30). Envelope, block header, transaction, receipt, log, eth_feeHistory. Post-London/Cancun optional fields marked optional. Self-authored from the Ethereum execution-apis specification. Not tested against providers.
Engineering safeguards
- G-01: No network requests carry user content: the CSP restricts connect-src to the site itself and no tool fetches anything. Verified in the smoke test by recording requests.
- G-02: Worker tasks are cancellable (terminate + respawn); stale results are discarded by task id.
- G-03/G-05: Drafts save with compare-and-set revisions; a stale tab gets a conflict prompt instead of overwriting.
- G-04: Storage failure switches the save bar to memory-only; export remains available.
- G-07: Imports are size-limited and parsed as data; malformed input stays editable.
Libraries
Keccak-256, SHA3-256 and SHA-256 come from @noble/hashes 1.8.0 (MIT, audited). The ABI codec is first-party and differentially tested against viem in the build's test suite; viem is not shipped to the browser. Fonts: Schibsted Grotesk and Martian Mono (SIL OFL), self-hosted.
Limits
Calldata up to 4 MiB, JSON inputs up to 16 MB, 20,000 logs per decode run and 200,000 decoded ABI values per payload. Performance figures are targets, not certified measurements.