# simulateHistoricalTransaction
## simulateHistoricalTransaction — Replay a transaction against historical state
> Replays a transaction against the archive's account state at a specified slot. Mirrors Solana's \`simulateTransaction\` response shape, pinned to historical state.\
> \
> \*\*Parameters\*\*\
> \
> 0\. \`transaction\` (required) — base64 (default) or base58 encoded transaction.\
> 1\. \`config\` (required) — see fields below. \`slot\` is required unless \`anchor\` is provided.
```json
{"openapi":"3.0.3","info":{"title":"Rewind RPC: simulateHistoricalTransaction","version":"1.0.0"},"tags":[{"name":"Rewind","description":"Historical transaction simulation."}],"servers":[{"url":"https://basic.rpc.solanavibestation.com","description":"Basic tier"},{"url":"https://ultra.rpc.solanavibestation.com","description":"Ultra tier"},{"url":"https://elite.rpc.solanavibestation.com","description":"Elite tier"},{"url":"https://epic.rpc.solanavibestation.com","description":"Epic tier"}],"security":[{},{"AuthHeader":[]},{"URLParameter":[]}],"components":{"securitySchemes":{"AuthHeader":{"type":"apiKey","in":"header","name":"Authorization","description":"Pass `Authorization: ` on each request."},"URLParameter":{"type":"apiKey","in":"query","name":"api_key","description":"Pass `?api_key=` on the URL."}},"schemas":{"Anchor":{"type":"object","required":["signature"],"properties":{"signature":{"type":"string","description":"Base58 transaction signature. The slot is derived automatically from the archive."},"position":{"type":"string","enum":["before","after"],"default":"before"}}},"JsonRpcEnvelope":{"type":"object","required":["jsonrpc","id"],"properties":{"jsonrpc":{"type":"string","enum":["2.0"]},"id":{"oneOf":[{"type":"string"},{"type":"integer"}]}}},"RewindContext":{"type":"object","required":["apiVersion","slot"],"properties":{"apiVersion":{"type":"string"},"slot":{"type":"integer","format":"int64","description":"The resolved query/load slot."}}},"SimulateValue":{"type":"object","required":["logs","unitsConsumed","rewindSlot","rewindLoadSlot"],"properties":{"err":{"type":"object","nullable":true,"additionalProperties":true,"description":"`null` on success; on failure, a structured `TransactionError` matching Solana's wire shape."},"logs":{"type":"array","description":"Program log stream from execution.","items":{"type":"string"}},"accounts":{"type":"array","description":"Post-state of the addresses listed in `config.accounts.addresses`, in order. Entries the tx didn't touch are emitted as null in the wire format.","items":{"type":"object","additionalProperties":true}},"unitsConsumed":{"type":"integer","format":"int64"},"returnData":{"type":"object","nullable":true,"additionalProperties":true,"description":"Program-emitted return data when set; null otherwise."},"innerInstructions":{"type":"array","description":"Present when `config.innerInstructions = true`. Each entry: `{ index, instructions[] }` — one per outer instruction that produced inner instructions.","items":{"type":"object","additionalProperties":true}},"rewindSlot":{"type":"integer","format":"int64","description":"Rewind extension. Natural slot used for ALT resolution."},"rewindLoadSlot":{"type":"integer","format":"int64","description":"Rewind extension. Slot at which non-ALT account state was loaded; equals `rewindSlot` unless `preStateSlot` overrode it."}}},"JsonRpcErrorResponse":{"type":"object","required":["jsonrpc","id","error"],"properties":{"jsonrpc":{"type":"string","enum":["2.0"]},"id":{"oneOf":[{"type":"string"},{"type":"integer"}]},"error":{"$ref":"#/components/schemas/JsonRpcError"}}},"JsonRpcError":{"type":"object","required":["code","message"],"description":"Method-specific codes:\n- `-32014` `slot` past the archive's `latestSlot`.\n- `-32015` `slot` older than the archive's `earliestSlot`.\n- `-32016` `anchor.signature` not indexed in the archive.\n- `-32017` FilteredAccountStale — tx touches an account in the filter set.\n- `-32018` SlotInArchiveGap — resolved load slot inside a known MISSING/UNKNOWN gap.\n- `-32603` Internal error. Treat as transient; safe to retry.\n","properties":{"code":{"type":"integer"},"message":{"type":"string"},"data":{"type":"object","additionalProperties":true}}}},"responses":{"UnauthorizedError":{"description":"Authentication required or invalid.","content":{"application/json":{"schema":{"$ref":"#/components/schemas/JsonRpcErrorResponse"}}}},"ForbiddenError":{"description":"Insufficient permissions for the request.","content":{"application/json":{"schema":{"$ref":"#/components/schemas/JsonRpcErrorResponse"}}}},"TooManyRequestsError":{"description":"Rate limit exceeded for this tier.","content":{"application/json":{"schema":{"$ref":"#/components/schemas/JsonRpcErrorResponse"}}}},"InternalServerError":{"description":"Unexpected server error. Treat as transient; safe to retry.","content":{"application/json":{"schema":{"$ref":"#/components/schemas/JsonRpcErrorResponse"}}}}}},"paths":{"/rewind":{"post":{"operationId":"simulateHistoricalTransaction","summary":"simulateHistoricalTransaction — Replay a transaction against historical state","tags":["Rewind"],"description":"Replays a transaction against the archive's account state at a specified slot. Mirrors Solana's `simulateTransaction` response shape, pinned to historical state.\n\n**Parameters**\n\n0. `transaction` (required) — base64 (default) or base58 encoded transaction.\n1. `config` (required) — see fields below. `slot` is required unless `anchor` is provided.\n","requestBody":{"required":true,"content":{"application/json":{"schema":{"type":"object","required":["jsonrpc","id","method","params"],"properties":{"jsonrpc":{"type":"string","enum":["2.0"]},"id":{"oneOf":[{"type":"string"},{"type":"integer"}]},"method":{"type":"string","enum":["simulateHistoricalTransaction"]},"params":{"type":"array","description":"Positional parameters [transaction, config].","minItems":2,"maxItems":2,"items":{"anyOf":[{"title":"transaction","type":"string","description":"Encoded transaction (base64 by default; configurable via `config.encoding`)."},{"title":"config","type":"object","properties":{"slot":{"type":"integer","format":"int64","description":"Required unless `anchor` is provided. Slot at which to load ALTs and account state."},"anchor":{"$ref":"#/components/schemas/Anchor"},"preStateSlot":{"type":"integer","format":"int64","description":"Advanced — load non-ALT account state at this slot instead of `slot`. Common pattern `slot - 1` for \"as if this tx ran at slot start\". Ignored when `anchor` is set."},"encoding":{"type":"string","enum":["base64","base58"],"default":"base64","description":"Encoding of the transaction parameter."},"innerInstructions":{"type":"boolean","default":false},"accounts":{"type":"object","description":"Post-state of these accounts is returned in `result.value.accounts`.","required":["encoding","addresses"],"properties":{"encoding":{"type":"string","enum":["base64"]},"addresses":{"type":"array","items":{"type":"string"},"description":"Base58 pubkeys."}}},"sigVerify":{"type":"boolean","description":"Accepted for compatibility; ignored."},"replaceRecentBlockhash":{"type":"boolean","description":"Accepted for compatibility; ignored."},"commitment":{"type":"string","description":"Accepted for compatibility; ignored."},"tolerateGaps":{"type":"boolean","default":false,"description":"When `false` (default), simulations whose resolved load slot lands inside a known MISSING/UNKNOWN gap return `-32018 SlotInArchiveGap`."}}}]}}}}}}},"responses":{"200":{"description":"Successful simulation. Failed transactions still return logs and `unitsConsumed`; the application-level error is reported in `result.value.err`.","content":{"application/json":{"schema":{"allOf":[{"$ref":"#/components/schemas/JsonRpcEnvelope"},{"type":"object","required":["result"],"properties":{"result":{"type":"object","required":["context","value"],"properties":{"context":{"$ref":"#/components/schemas/RewindContext"},"value":{"$ref":"#/components/schemas/SimulateValue"}}}}}]}}}},"401":{"$ref":"#/components/responses/UnauthorizedError"},"403":{"$ref":"#/components/responses/ForbiddenError"},"429":{"$ref":"#/components/responses/TooManyRequestsError"},"500":{"$ref":"#/components/responses/InternalServerError"}}}}}}
```
---
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