trace_call

trace_call simulates a call against a chosen Polygon PoS block state and returns the result in the OpenEthereum/Parity format, with no transaction broadcast and no MATIC spent. You pick exactly which detail you want through traceTypes: the trace call tree, an opcode-level vmTrace, and a stateDiff showing balance, nonce, code, and storage changes. Send the request to https://polygon.therpc.io/YOUR_API_KEY (chain ID 137, 0x89). It simulates the call against the given block state and returns an OpenEthereum-style call-tree trace, optional VM trace, and optional state diff — without creating a transaction.

Use cases

• Preview every internal call a Polygon transaction would generate before broadcasting it, with traceTypes: ["trace"].
• Diff storage state with stateDiff to confirm a prospective transaction changes exactly the slots you expect on a Polygon DeFi contract.
• Test contract logic against a historical Polygon block state by pinning blockParameter (past blocks need a Bor archive node).

Parameters

Response

Example request

1curl https://polygon.therpc.io/YOUR_API_KEY \
2  -X POST \
3  -H "Content-Type: application/json" \
4  -d '{
5    "jsonrpc": "2.0",
6    "method": "trace_call",
7    "params": [
8        {
9          "to": "0x0000000000000000000000000000000000000000",
10          "data": "0x"
11        },
12        [
13          "trace"
14        ],
15        "latest"
16      ],
17    "id": 1
18  }'

Try it live in the Polygon playground.

Errors & troubleshooting

Common pitfalls

• Asking for all three trace types at once (trace + vmTrace + stateDiff) can balloon the response on a busy Polygon contract — request only the types you actually consume.
• Simulating against a historical block state requires a trace-enabled Bor archive node, not a plain full node.
• The vmTrace format is Parity-specific and does not match Bor's Geth-style debug_traceCall struct-log — do not feed one into a parser written for the other.

Supported networks

• Mainnet — Chain ID: 137
• Amoy — Chain ID: 80002

See also

• trace_transaction
• debug_traceCall
• trace_replayTransaction
• trace_filter

1curl https://polygon.therpc.io/YOUR_API_KEY \
2  -X POST \
3  -H 'Content-Type: application/json' \
4  -d '{"jsonrpc":"2.0","id":1,"method":"trace_call","params":[{"to":"0x0000000000000000000000000000000000000000","data":"0x"},[],"latest"]}'