---
title: "List Capabilities"
method: GET
path: "/api/capabilities"
tags: ["Capabilities", "Fabric"]
---

# List Capabilities

`GET /api/capabilities`

## Request

- Base URL: `https://api.agentstack.tech` (the document declares no server; this is the origin it was published from)
- URL: `https://api.agentstack.tech/api/capabilities`
- Auth: one of:
  - API key in header `X-API-Key`
  - HTTP bearer

Return descriptor catalog entries visible to the caller (L1 cap filtered).

## Query parameters

- `domain` string, nullable: Filter by domain prefix
- `surface` string, nullable: Filter by surface (mcp, ptc, …)
- `effective` boolean: Merge live @mcp_tool schema + fixture overlay (default)

## Response `200`

Successful Response

- object

## Other responses

- `400`: Bad Request
- `401`: Unauthorized
- `403`: Forbidden
- `404`: Not Found
- `409`: Conflict
- `422`: Validation Error
- `429`: Too Many Requests
- `500`: Internal Server Error

---

[API](https://skmtc.dev/agentstack/apis/agentstack-core-api.md) · [All operations](https://skmtc.dev/agentstack/apis/agentstack-core-api/llms.txt) · [OpenAPI document](https://skmtc.dev/agentstack/apis/agentstack-core-api/revisions/79f4a4dd8813?raw)