# Triage · Decay

`station__algovigilance__triage-decay` · external (needs EXECUTION_BACKEND_URL configured) · domain `algovigilance` · pv-relevance `pv-core`

Compute decay-adjusted relevance for a drug-event signal. Exponential decay model with configurable half-life — fresh signals weigh more, stale ones fade.

> **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

- `drug` *string* (required) — Drug name or RxCUI
- `event` *string* (required) — Adverse event term (MedDRA preferred)
- `half_life_days` *string* — Exponential decay half-life. Default 30.

## Example call

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

{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "station__algovigilance__triage-decay",
    "arguments": {
      "drug": "ozempic",
      "event": "thyroid c-cell hyperplasia",
      "half_life_days": 30
    }
  }
}
```

## Related

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