{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "https://openwop.dev/spec/v1/compact-tool-descriptor.schema.json",
  "title": "CompactToolDescriptor",
  "description": "RFC 0112. A lossy, model-facing projection of `ToolDescriptor` (tool-descriptor.schema.json) returned by `GET /v1/tools?view=compact` + `GET /v1/tools/{toolId}?view=compact` when the host advertises `capabilities.toolCatalog.compactView: true`. Heavy descriptive fields (`outputSchema`, `auth`, `egress`, `approval`, `replayPolicy`, `costHint`, `latencyHint`) are dropped, and any `inputSchema` is bounded to the self-contained compact structural subset (top-level `type: \"object\"` with `properties`; no `$ref`/`oneOf`/`allOf`/`anyOf`/`not`/`patternProperties`/`dependentSchemas`). The subset is the stable structural core of RFC 0030 Tier-1, cited as rationale but pinned HERE so conformance is machine-checkable and immune to that informative table's drift. Like the full descriptor, a CompactToolDescriptor never carries credential material (SR-1) and is not an invocation path.",
  "type": "object",
  "additionalProperties": false,
  "required": ["toolId", "source", "safetyTier"],
  "properties": {
    "toolId": {
      "type": "string",
      "minLength": 1,
      "description": "Unchanged from ToolDescriptor. Stable, host-unique tool identifier in the `<scope>:<tool-id>` form; MUST be stable across catalog reads for a given host version (tool-catalog.md §C MUST 3). The compact `tools[]` MUST carry the same `toolId` set as the standard view for the same principal (projection completeness)."
    },
    "source": {
      "type": "string",
      "enum": ["node-pack", "workflow", "mcp", "connector", "host-extension"],
      "description": "Retained from ToolDescriptor so the `safetyTier: \"exec\" ⇒ source: \"host-extension\"` cross-field MUST (RFC 0069) stays expressible. Which surface backs the tool: `node-pack`/`workflow`/`mcp`/`connector`/`host-extension`."
    },
    "safetyTier": {
      "type": "string",
      "enum": ["pure", "read", "write", "exec"],
      "description": "REQUIRED. The tool's DATA-EFFECT classification (`pure`/`read`/`write`/`exec`); per RFC 0069 an `exec` tool MUST be `source: \"host-extension\"`. Host-assigned, not derivable from a permission/approval/risk tier."
    },
    "title": { "type": "string", "description": "MAY — short human-readable label for a model-facing tool picker." },
    "description": {
      "type": "string",
      "description": "MAY — one-line summary; the host SHOULD truncate to a model-facing summary in the compact view."
    },
    "inputSchema": {
      "type": "object",
      "description": "MAY — the tool's argument schema bounded to the compact structural subset (RFC 0112). When present it MUST have top-level `type: \"object\"` with an explicit `properties` map, and MUST NOT use `$ref`, `oneOf`, `allOf`, `anyOf`, `not`, `patternProperties`, or `dependentSchemas` AT ANY NESTING DEPTH (including inside nested property schemas). Absent ⇒ opaque/host-interpreted args. NOTE: the `propertyNames` clause below is a TOP-LEVEL structural floor only; the total any-depth constraint is enforced by the RFC 0112 conformance scenario (a schema-aware recursive walk), since pure JSON Schema cannot express it without recursion gymnastics.",
      "required": ["type", "properties"],
      "properties": {
        "type": { "const": "object", "description": "Top-level MUST be `\"object\"`." },
        "properties": { "type": "object", "description": "The argument property map (MUST be present)." }
      },
      "propertyNames": {
        "$comment": "RFC 0112 compact structural subset (TOP-LEVEL FLOOR): forbid the heavy/non-portable keywords as top-level inputSchema keys. The total any-depth constraint is enforced by conformance.",
        "not": { "enum": ["$ref", "oneOf", "allOf", "anyOf", "not", "patternProperties", "dependentSchemas"] }
      }
    }
  },
  "allOf": [
    {
      "$comment": "RFC 0069 / tool-catalog.md §C-1: an exec-tier tool MUST be host-extension-sourced (exec is never protocol-tier). Mirrors tool-descriptor.schema.json.",
      "if": { "properties": { "safetyTier": { "const": "exec" } }, "required": ["safetyTier"] },
      "then": { "properties": { "source": { "const": "host-extension" } }, "required": ["source"] }
    }
  ]
}