# audio-spec-compute

`station__audio__audio-spec-compute` · external (needs EXECUTION_BACKEND_URL configured) · domain `audio` · pv-relevance `non-pv`

Compute audio spec properties (bytes/frame, bytes/sec, duration).

> **Note:** This tool routes through an external execution backend. If `EXECUTION_BACKEND_URL` is unset on the server, calls return JSON-RPC error `-32603 "Tool execution backend not configured"`. Tools with `backend: native` execute in-process and are always callable.

## Agent metadata

- `idempotent`: unknown
- `read_only`: unknown
- `expected_latency_ms`: unknown (not yet contract-tested)
- `cost_tokens_estimate`: unknown

## Input schema

- `bytes` *integer* — Optional: byte count to compute duration for.
- `duration_secs` *number* — Optional: duration in seconds to compute byte count for.
- `format` *string* (required) — Sample format: "s16", "s24", "s32", "f32", or "u8".
- `layout` *string* (required) — Channel layout: "mono", "stereo", "surround_51", "surround_71", or a channel count.
- `rate` *integer* (required) — Sample rate in Hz (e.g., 44100, 48000, 96000) or preset name.

## Example call

```json
POST /api/mcp
Content-Type: application/json

{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "station__audio__audio-spec-compute",
    "arguments": {
      "format": "",
      "layout": "",
      "rate": 0
    }
  }
}
```

## Related

- [/tools](/tools) — all 3062 tools
- [/tools/audio__audio-spec-compute](/tools/audio__audio-spec-compute) — HTML page
- [/tools/audio__audio-spec-compute/json](/tools/audio__audio-spec-compute/json) — JSON form (agent-friendly)
- [/api/mcp](/api/mcp) — endpoint
- [/AGENTS.md](/AGENTS.md) — agent guide