# functions

`station__pvdsl__functions` · external (needs EXECUTION_BACKEND_URL configured) · domain `pvdsl` · pv-relevance `pv-core`

List all available PVDSL native functions organized by namespace. Namespaces: signal (prr, ror, ic, ebgm, chi_square, fisher, sprt, maxsprt, cusum, mgps), causality (naranjo, who_umc, rucam), meddra (levenshtein, similarity), risk (sar, es, monte_carlo), date (now, diff_days), classify (hartwig_siegel), math (abs, sqrt, pow, log, ln, exp, min, max, floor, ceil, round), chem (arrhenius, michaelis, hill, henderson, halflife, sqi).

> **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

No inputs required.

## Example call

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

{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "station__pvdsl__functions",
    "arguments": {}
  }
}
```

## Related

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