Call frames of a transaction, paged

See this trace in TraceFast →

The whole call tree of a transaction, frame by frame in the order it ran, page by page. Each frame carries everything the execution trace carries, plus — always — the first 260 bytes of its calldata and output with their full sizes, and the positions of the event logs it emitted.

Use this method when a tree is larger than the trace's 1 000-frame cap, or when you need every frame's calldata or the logs a frame emitted. For a small tree read in one response, the execution trace is simpler.

GET https://tracefast.xyz/api/v1/chains/1/traces/{hash}/frames

Access — an API key on the Investigation plan or higher (plans), or no key at all: pay per call with x402 at the same path on https://mpp.tracefast.xyz/api/v1, at the price its 402 states. As a tool for AI agents: get_trace_frames on the MCP server. Stable — see stability.

chains/1 is a literal: the method serves Ethereum mainnet data. Other chain ids answer 404 chain_not_supported. There are no other parameters — an unknown one is refused rather than ignored.

What it covers, and what it does not

• Up to 20 000 frames. The method walks the tree to that size; when it is larger, the last page says so with framesTruncated: true. A clipped tree never claims to be the whole one.
• order is the position in the whole tree, not in the page: a page that starts at order 50 continues the one that ended at 49.
• A page may hold fewer frames than limit when their calldata is large. It still continues from the last frame served; only an absent nextCursor ends the walk.
• A trace that is not available yet is refused, never answered empty. Traces trail the chain by minutes to hours, sometimes longer. A transaction in a block they have not reached answers 422 block_not_available with reason: coverage_gap and the last block traces are available for. That says nothing about the transaction's outcome — ask again later.
• Frames and their log positions have a starting block. meta.coverage names the first block the frames are computed from (framesFromBlock) and the first block the event attribution is computed from (eventAttributionFromBlock). Both can move to earlier blocks over time.

Response

200 application/json, here with ?limit=1 — the first page of a USDC transfer through its proxy:

{
  "data": {
    "hash": "0xc41b41fb1c3eea59ea87b9e90edf476fb202e8daf02f19f469cdf497adbc76e0",
    "blockNumber": 25920000,
    "txIndex": 3,
    "frames": [
      {
        "order": 0,
        "depth": 1,
        "callPath": "0000",
        "callType": "call",
        "from": "0x978e75381d64fb18af7112e42fa76a211a773456",
        "to": "0xa0b86991c6218b36c1d19d4a2e9eb0ce3606eb48",
        "valueWei": "0",
        "gas": "78392",
        "gasUsed": "40652",
        "inputSelector": "0xa9059cbb",
        "status": "success",
        "revertDecodeStatus": "absent",
        "codeAddress": "0xa0b86991c6218b36c1d19d4a2e9eb0ce3606eb48",
        "inputHead": "0xa9059cbb000000000000000000000000f9dec5642e2b51ba67c695144d3360fab966f5a30000000000000000000000000000000000000000000000000000000029ba1944",
        "inputSize": 68,
        "outputHead": "0x0000000000000000000000000000000000000000000000000000000000000001",
        "outputSize": 32,
        "logIndexes": []
      }
    ],
    "framesTruncated": false,
    "nextCursor": "AVsyNTkyMDAwMCwzLDBdr7mkLJEtmSoLlzCQTIJIQw"
  },
  "meta": {
    "chain": "ethereum",
    "timestamp": 1789063644283,
    "cached": false,
    "asOfBlock": 25920000,
    "docs": "https://docs.tracefast.xyz/api/trace-frames",
    "coverage": {
      "eventAttributionFromBlock": 2675000,
      "framesFromBlock": 2675000
    }
  }
}

The second page holds frame order: 1 — the proxy's delegatecall into its implementation — with logIndexes: [0]: the Transfer event was emitted by the implementation's code, not by the outer call. That page carries no nextCursor, so the tree has two frames.

data

A frame

A frame has every field of a frame in the execution trace — its position (callPath, parentPath), the call, value and gas, what it created (createdAddress, salt, initCodeHash, selfdestructBeneficiary) and its outcome (errorKind, errorSelector, revertReason, revertData, revertDataSize, revertDataTruncated) — with two differences:

meta.coverage

Pagination

Pages are keyset, not offset. Pass nextCursor back as cursor until it is absent; keep the same hash. A cursor opens only for this method and this transaction; any other use, or a cursor altered in transit, answers 400 invalid_cursor — restart from the first page. See pagination.

Errors

Malformed input, unknown parameters and the key check's 401/403/429 are the same for every method — see conventions and API keys.

Related pages

• Execution trace of a transaction — the same tree in one response, up to 1 000 frames, calldata opt-in
• Transaction events — the logs that logIndexes point at
• Storage writes of a transaction — what each frame wrote to contract storage
• Why a transaction reverted — only the failed frames, with error names
• Transactions: Trace — the call tree in the app

Last updated 22 Oct 2026, 08:06 UTC · verified against TraceFast v1.0.261 · Markdown