Agent Spec — Compact OAS Flow (`oas.json`)

See also: packages/agents/AGENTS.md — implementation details

Canonical filename: The canonical on-disk path is agents/<vendor>/<slug>/cinatra/oas.json. The loader/handlers also recognise agents/<slug>/cinatra/agent.json and agents/<slug>/agent.json as transitional fallbacks, but all new agents MUST be written as oas.json in the vendor-namespaced path. Both the live Model Context Protocol (MCP) schemas and the runtime resolver (resolveAgentJsonPath) treat oas.json as the only canonical name. References to agent.json below are about example content, not the canonical on-disk filename.

The file content uses the compact Open Agent Specification (OAS) Flow 26.1.0 format. Root-level fields are now agentspec_version: "26.1.0" and component_type: "Flow"; all Cinatra-specific metadata lives under metadata.cinatra. This document is the canonical reference. The filename agent-spec.md is retained for link stability — the current format is NOT v2; it is OAS Flow. See the ## What Changed table below for the full legacy → current mapping.

Related docs:

references/platform/agent-packaging.md — layout conventions, templates, install paths
references/platform/ensure-agent-package.md — startup scan + ZIP install mechanics
packages/agents/src/oas-compiler.ts — live compiler (source of truth for derivation)
packages/agents/src/validate-agent-json.ts — live validator (source of truth for rejection rules)
packages/agents/AGENTS.md §OAS compiler — package-scoped reference

What Changed (v2 → OAS Flow)

v2 (nested)	OAS Flow (compact)
`componentType: "Agent"` at root	`component_type: "Flow"` at root
`metadata.cinatra.formatVersion: 2`	`agentspec_version: "26.1.0"` at root
`metadata.cinatra.inputSchema` (authored)	derived by compiler from `StartNode.inputs`
`metadata.cinatra.outputSchema` (authored)	derived by compiler from `EndNode.outputs`
`metadata.cinatra.prompt` (authored)	sourced from `Agent.system_prompt` component
`metadata.cinatra.taskSpec` (authored)	rejected — moved to SKILL.md / `Agent.system_prompt`
`metadata.cinatra.approvalPolicy` (authored)	derived from AgentNodes by compiler
`metadata.cinatra.compiledPlan` (authored)	rejected — always `[]`, produced at compile time
`validateAgentJsonV2()`	`validateOasAgentJson()`
`AgentJsonV2` type	DELETED

Full OAS Flow Shape

{
  "agentspec_version": "26.1.0",
  "component_type": "Flow",
  "id": "email-recipients-flow",
  "name": "Recipient Generator",
  "metadata": {
    "cinatra": {
      "type": "leaf",
      "hitlScreens": [
        "@cinatra-ai/email-outreach-agent:list-picker",
        "@cinatra-ai/reviewer-agent:output"
      ]
    }
  },
  "inputs": [
    { "title": "campaignId", "type": "string", "format": "uuid" },
    { "title": "accountScope", "type": "object" }
  ],
  "outputs": [
    { "title": "campaignId", "type": "string", "format": "uuid" },
    { "title": "recipientCount", "type": "integer" },
    { "title": "confirmedRecipients", "type": "array", "items": { "type": "object" } }
  ],
  "start_node": { "$component_ref": "start" },
  "nodes": [
    { "$component_ref": "start" },
    { "$component_ref": "generate" },
    { "$component_ref": "end" }
  ],
  "control_flow_connections": [
    {
      "component_type": "ControlFlowEdge",
      "name": "start_to_generate",
      "from_node": { "$component_ref": "start" },
      "to_node": { "$component_ref": "generate" }
    },
    {
      "component_type": "ControlFlowEdge",
      "name": "generate_to_end",
      "from_node": { "$component_ref": "generate" },
      "to_node": { "$component_ref": "end" }
    }
  ],
  "data_flow_connections": [
    {
      "component_type": "DataFlowEdge",
      "name": "start_to_generate_campaignId",
      "source_node": { "$component_ref": "start" },
      "source_output": "campaignId",
      "destination_node": { "$component_ref": "generate" },
      "destination_input": "campaignId"
    }
  ],
  "$referenced_components": {
    "start": {
      "component_type": "StartNode",
      "id": "start",
      "name": "Inputs",
      "metadata": {
        "cinatra": {
          "required": ["campaignId", "accountScope"],
          "hidden": ["campaignId"],
          "inputRenderers": {
            "accountScope": "@cinatra-ai/email-outreach-agent:list-picker"
          }
        }
      },
      "inputs": [
        { "title": "campaignId", "type": "string", "format": "uuid" },
        { "title": "accountScope", "type": "object" }
      ]
    },
    "generate": {
      "component_type": "AgentNode",
      "id": "generate",
      "name": "Generate recipient list",
      "metadata": {
        "cinatra": {
          "riskClass": "read_only",
          "requiresApproval": true,
          "renderer": "@cinatra-ai/email-recipient-selection-agent:output",
          "a2uiSurfaceId": "email-recipients:step-1:output"
        }
      },
      "agent": { "$component_ref": "agent-recipients" }
    },
    "end": {
      "component_type": "EndNode",
      "id": "end",
      "name": "End",
      "outputs": [
        { "title": "campaignId", "type": "string", "format": "uuid" },
        { "title": "recipientCount", "type": "integer" },
        { "title": "confirmedRecipients", "type": "array", "items": { "type": "object" } }
      ]
    },
    "agent-recipients": {
      "component_type": "Agent",
      "id": "agent-recipients",
      "name": "Recipient generator agent",
      "llm_config": { "$component_ref": "shared-llm-config" },
      "toolboxes": [{ "$component_ref": "cinatra-mcp-toolbox" }],
      "system_prompt": "You are a campaign recipient selection agent...",
      "metadata": {
        "cinatra": {
          "packageName": "@cinatra-ai/email-recipient-selection-agent"
        }
      }
    }
  }
}

Field Reference

Top-level fields

Field	Type	Required	Notes
`agentspec_version`	`"26.1.0"` (literal)	Yes	Anything else is rejected by `validateOasFlowStructural`.
`component_type`	`"Flow"` (literal)	Yes	Identifies the compact OAS envelope.
`id`	`string`	Yes	Stable human-readable id (convention: `<slug>-flow`).
`name`	`string`	Yes	Display name.
`metadata.cinatra.type`	`"leaf" \| "orchestrator" \| "node" \| "flow"`	Yes	Determines compile topology. The compiler accepts both the legacy values (`leaf` / `orchestrator`) and the OAS-aligned ones (`node` / `flow`).
`metadata.cinatra.hitlScreens`	`string[]`	No	Namespaced `@<vendor>/<package-slug>:<renderer-id>` ids of human-in-the-loop (HITL) renderers this agent may emit (e.g. `@cinatra-ai/email-outreach-agent:list-picker`).
`inputs`	`PropertySchema[]`	Yes	Flat JSON Schema property list — compiler derives `inputSchema` from this + StartNode.
`outputs`	`PropertySchema[]`	Yes	Flat JSON Schema property list — compiler derives `outputSchema` from EndNode.
`start_node`	`{ $component_ref: string }`	Yes	Must resolve to a StartNode inside `$referenced_components`.
`nodes`	`{ $component_ref: string }[]`	Yes	All flow nodes (Start + all AgentNodes + End). Array order is NOT execution order — see BFS topology.
`control_flow_connections`	`ControlFlowEdge[]`	Yes	Compiler traverses these to derive step order.
`data_flow_connections`	`DataFlowEdge[]`	No	Compiler uses these to derive per-step `inputMapping`.
`$referenced_components`	`Record<string, unknown>`	Yes	Local component registry. Must contain exactly one StartNode and exactly one EndNode (validator cases 40, 41).

StartNode `metadata.cinatra` extensions

Field	Type	Required	Notes
`required`	`string[]`	No	Input ids that must be present in `agent_runs.inputParams` before the setup interrupt loop falls through to runtime (WayFlow) dispatch.
`hidden`	`string[]`	No	Input ids suppressed from the setup form UI. Compiler still threads them into `inputSchema`.
`inputRenderers`	`Record<string, string>`	No	Maps input id → namespaced `x-renderer` id (e.g. `@cinatra-ai/email-outreach-agent:cta`).
`inputTitles`	`Record<string, string>`	No	Human-readable label overrides per input id, shown in the setup UI.

AgentNode `metadata.cinatra` extensions

Field	Type	Required	Notes
`riskClass`	`string`	No	Surfaced as `step.riskClass` for UI risk badges (e.g. `"read_only"`, `"send_external_message"`).
`requiresApproval`	`boolean`	No	Drives HITL gate. Leaf defaults may apply via `mergeParentLeafCinatra`.
`renderer`	`string`	No	Namespaced `x-renderer` id; emitted as `step.xRenderer` in compiled output.
`a2uiSurfaceId`	`string`	No	agent-to-UI (A2UI) protocol catalog surface id. Emitted as `step.a2uiSurfaceId`.
`a2uiSurfaceIdOverride`	`string`	No	Consumed by `mergeParentLeafCinatra`; never re-emitted in compiled output. Only valid when `hitlOwnedBy === "childAgent"`.
`hitlOwnedBy`	`"childAgent" \| "self"`	No	Indicates which actor gates HITL. `"childAgent"` = defer to sub-agent’s own approval policy; `"self"` = this step gates.
`description`	`string`	No	Prose shown in admin views.

Object type annotations

Cinatra agents may declare the object types they produce as output. The declaration is placed inline on the output port that carries the object’s id, as a cinatra custom keyword directly on the JSON Schema property. This follows OAS 26.1.0 §6.3 which defines output ports as JSON Schema Property objects and permits custom keyword annotations inline.

Schema (snake_case in JSON, all fields except object_type are optional):

outputs[*].cinatra?: {
  object_type: string;         // @scope/package:local-id (validated at compile time)
  display_name?: string;       // Human-readable label (defaults to port title)
  category?: "profile" | "content" | "project" | "idea" | "report"; // defaults to "report"
  canonical_keys?: string[];   // Identity-resolution keys for dedup
  identity_key?: string;       // Data field used as Graphiti dedup key (e.g. "cinatra_agent_run_id")
};

Compile-time validation:

Each object_type is validated against the namespace regex /^@[\w-]+\/[\w-]+:[\w-]+$/. Failed entries return { ok: false, error: ... }.
Type IDs already registered statically by @cinatra/* packages are accepted; the install hook skips creating a duplicate dynamic row. A category mismatch with the static registration emits console.warn but does not fail compile.
Type IDs not statically registered are inserted into cinatra.dynamic_object_types at install time with source: "install", status: "active".

Example (orchestrator outputting a campaign id):

{
  "metadata": {
    "cinatra": { "type": "orchestrator" }
  },
  "outputs": [
    {
      "title": "campaignId",
      "type": "string",
      "format": "uuid",
      "cinatra": {
        "object_type": "@cinatra/campaigns:campaign",
        "display_name": "Email Outreach Campaign",
        "category": "project",
        "canonical_keys": ["name", "offeringCompanyWebsite", "cinatraAgentRunId"],
        "identity_key": "cinatra_agent_run_id"
      }
    }
  ]
}

Lifecycle: classifier proposes → admin approves → MCP register → agent install registers.

Validator Rules

Implemented in packages/agents/src/validate-agent-json.ts (validateOasAgentJson):

validateOasFlowStructural — Zod parse of flowSchema (agentspec_version=26.1.0, component_type=Flow, required arrays).
Root-level legacy field rejection: componentType (leftover from v2).
metadata.cinatra legacy-field rejection: formatVersion, executionMode, approvalPolicy, compiledPlan, inputSchema, outputSchema, prompt, taskSpec.
Per-AgentNode semantic checks: hitlOwnedBy ∈ {childAgent, self}, a2uiSurfaceIdOverride only valid when hitlOwnedBy === "childAgent", requiresApproval boolean.
Case 38 — every $component_ref resolves locally OR against the known global registry ids (shared-llm-config, cinatra-mcp-toolbox, a2a-default-connection).
Case 39 — no duplicate node ids in the nodes array.
Case 40 — exactly one StartNode in $referenced_components.
Case 41 — exactly one EndNode in $referenced_components.

Component Registry (Two-Tier Lookup)

Component references ({ "$component_ref": "<id>" }) resolve through a two-tier lookup: first against the flow’s local $referenced_components map, then against the global registry at agents/_shared/cinatra/components.json. An unresolved id throws; cycles throw too (the walker tracks visited per resolution pass).

Tier	Source	Behavior on miss
1 — Local	`parsed.$referenced_components`	Fall through to tier 2
2 — Global	`agents/_shared/cinatra/components.json`	Throw `unresolved component ref: {id}`
(cycle)	`visited: Set<string>` per walk	Throw `cycle detected at component id {id}`

// From packages/agents/src/oas-compiler.ts:223-238
function resolveComponentRef(
  id: string,
  localRefs: Record<string, unknown>,
  globalRegistry: Record<string, unknown>,
  visited: Set<string>,
): Record<string, unknown> {
  if (visited.has(id)) throw new Error(`cycle detected at component id ${id}`);
  visited.add(id);
  const local = localRefs[id];
  if (local && typeof local === "object") return local as Record<string, unknown>;
  const global = globalRegistry[id];
  if (global && typeof global === "object") return global as Record<string, unknown>;
  throw new Error(
    `unresolved component ref: ${id} (looked in local $referenced_components and global registry)`,
  );
}

{
  "$schema": "/schemas/cinatra/oas-component-registry.schema.json",
  "agentspec_version": "26.1.0",
  "components": {
    "shared-llm-config": {
      "component_type": "OpenAiConfig",
      "id": "shared-llm-config",
      "name": "Shared LLM config",
      "model_id": "gpt-4o",
      "api_type": "chat_completions",
      "metadata": { "cinatra": { "resolvedAtRuntime": true } }
    },
    "cinatra-mcp-toolbox": {
      "component_type": "MCPToolBox",
      "id": "cinatra-mcp-toolbox",
      "name": "Cinatra MCP Server",
      "metadata": { "cinatra": { "resolvedAtRuntime": true } },
      "client_transport": {
        "component_type": "StreamableHTTPTransport",
        "id": "cinatra-mcp-transport",
        "name": "Cinatra MCP transport",
        "url": "/api/mcp"
      }
    },
    "a2a-default-connection": {
      "component_type": "A2AConnectionConfig",
      "id": "a2a-default-connection",
      "name": "Default A2A connection",
      "timeout": 600,
      "verify": true
    }
  }
}

Do not add per-package components.json files. Package-specific Agent / A2AAgent / ServerTool components live under each agent.json’s $referenced_components map. Only truly shared infrastructure (large language model (LLM) config, MCP toolbox, agent-to-agent (A2A) protocol connection) lives in the global registry.

BFS Topology

Step order follows breadth-first search (BFS) from start_node via control_flow_connections, NOT the parsed.nodes array index (peer-review fix #2). The compiler:

Builds an adjacency map from control_flow_connections (from_node.$component_ref → to_node.$component_ref).
Deduplicates identical (from, to) edges inline (oas-compiler.ts:495) so queue operations are not wasted and step ordering is not muddled.
Seeds the BFS queue from parsed.start_node.$component_ref.
Appends any disconnected nodes in array order as a safety net (oas-compiler.ts:511); the structural validator should reject the upstream condition before compile is reached.
Assigns stepNumber 1-indexed across the BFS-ordered AgentNodes only — StartNode and EndNode are never steps.

The BFS topology guarantees that adding a new linear leaf or re-ordering the nodes array does not change emitted step order: only the control_flow graph shape determines step sequence.

Compiled Output (CompiledAgentOas)

compileOasAgentJson returns a discriminated union (peer-review fix #1) — callers branch on .ok instead of the legacy null-or-throw mix:

// From packages/agents/src/oas-compiler.ts:386-397
export type CompiledAgentOas = {
  approvalPolicy: { steps: CompiledAgentOasStep[] };
  inputSchema: Record<string, unknown>;
  outputSchema: Record<string, unknown> | null;
  prompt: string | null;
  packageName: string | null;
  packageVersion: string | null;
  agentDependencies: Record<string, string>;
  type: "leaf" | "orchestrator";
  compiledPlan: [];
  hitlScreens: string[];
};

// From packages/agents/src/oas-compiler.ts:371-384
export type CompiledAgentOasStep = {
  stepNumber: number;
  riskClass?: string;
  requiresApproval: boolean;
  xRenderer?: string;
  description?: string;
  name?: string;
  a2uiSurfaceId?: string;
  hitlOwnedBy?: "childAgent" | "self";
  childAgent?: {
    packageName: string;
    inputMapping: Record<string, string>;
  };
};

The CompileOasResult union has two branches:

// From packages/agents/src/oas-compiler.ts:400-402
export type CompileOasResult =
  | { ok: true; value: CompiledAgentOas }
  | { ok: false; error: string };

Reference Files

Role	Path
Orchestrator	`email-outreach-agent` repo → `cinatra/oas.json`
Leaf	`email-recipient-selection-agent` repo → `cinatra/oas.json`
Leaf	`email-drafting-agent` repo → `cinatra/oas.json`
Leaf	`reviewer-agent` repo → `cinatra/oas.json`
Leaf	`email-delivery-agent` repo → `cinatra/oas.json`
Global registry	`<agent-install-dir>/_shared/cinatra/components.json` (resolved via `resolveAgentInstallDir()` in `oas-compiler.ts`)
Compiler source	`packages/agents/src/oas-compiler.ts`
Validator source	`packages/agents/src/validate-agent-json.ts`

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