from __future__ import annotations import base64 import json import re from typing import Any import httpx from deepagents import create_deep_agent from langchain_core.messages import BaseMessage from langchain_core.tools import StructuredTool from langchain_openai import ChatOpenAI from pydantic import BaseModel, Field from a2a_pack import ( A2AAgent, ConsumerSetup, ConsumerSetupField, ConsumerSetupMissing, EgressPolicy, LLMProvisioning, Pricing, Resources, RunContext, skill, ) DEFAULT_BASE_URL = "https://blog.a2acloud.io" OPERATIONS = json.loads("{\n \"create_blog_post\": {\n \"description\": \"Create a blog post\",\n \"destructive\": true,\n \"method\": \"POST\",\n \"operation_id\": \"create_blog_post\",\n \"parameters\": [],\n \"path\": \"/api/posts\",\n \"request_body\": {\n \"$ref\": \"#/components/schemas/BlogPostInput\"\n },\n \"security\": [\n {\n \"bearerAuth\": []\n },\n {\n \"apiKeyAuth\": []\n }\n ],\n \"skill_name\": \"create_blog_post\",\n \"summary\": \"Create a blog post\",\n \"tags\": [\n \"Posts\"\n ]\n },\n \"delete_blog_post\": {\n \"description\": \"Delete a post by slug\",\n \"destructive\": true,\n \"method\": \"DELETE\",\n \"operation_id\": \"delete_blog_post\",\n \"parameters\": [],\n \"path\": \"/api/posts/{slug}\",\n \"request_body\": null,\n \"security\": [\n {\n \"bearerAuth\": []\n },\n {\n \"apiKeyAuth\": []\n }\n ],\n \"skill_name\": \"delete_blog_post\",\n \"summary\": \"Delete a post by slug\",\n \"tags\": [\n \"Posts\"\n ]\n },\n \"get_blog_health\": {\n \"description\": \"Check blog service health\",\n \"destructive\": false,\n \"method\": \"GET\",\n \"operation_id\": \"get_blog_health\",\n \"parameters\": [],\n \"path\": \"/api/healthz\",\n \"request_body\": null,\n \"security\": null,\n \"skill_name\": \"get_blog_health\",\n \"summary\": \"Check blog service health\",\n \"tags\": [\n \"Health\"\n ]\n },\n \"get_blog_post\": {\n \"description\": \"Returns a published post. Add `preview=1` to fetch drafts or future-dated posts; preview requests require either bearer auth or the `x-api-key` header.\",\n \"destructive\": false,\n \"method\": \"GET\",\n \"operation_id\": \"get_blog_post\",\n \"parameters\": [\n {\n \"description\": \"Set to `1` to bypass the public published-post filter. Requires authentication.\",\n \"in\": \"query\",\n \"name\": \"preview\",\n \"required\": false,\n \"schema\": {\n \"enum\": [\n \"1\"\n ],\n \"type\": \"string\"\n }\n }\n ],\n \"path\": \"/api/posts/{slug}\",\n \"request_body\": null,\n \"security\": [\n {},\n {\n \"bearerAuth\": []\n },\n {\n \"apiKeyAuth\": []\n }\n ],\n \"skill_name\": \"get_blog_post\",\n \"summary\": \"Get a post by slug\",\n \"tags\": [\n \"Posts\"\n ]\n },\n \"list_blog_posts\": {\n \"description\": \"Returns published posts by default. `status=all` and `status=draft` include draft content and require either bearer auth or the `x-api-key` header.\",\n \"destructive\": false,\n \"method\": \"GET\",\n \"operation_id\": \"list_blog_posts\",\n \"parameters\": [\n {\n \"description\": \"Use `published` or omit the parameter for public published posts. `all` and `draft` require authentication.\",\n \"in\": \"query\",\n \"name\": \"status\",\n \"required\": false,\n \"schema\": {\n \"default\": \"published\",\n \"enum\": [\n \"published\",\n \"draft\",\n \"all\"\n ],\n \"type\": \"string\"\n }\n }\n ],\n \"path\": \"/api/posts\",\n \"request_body\": null,\n \"security\": [\n {},\n {\n \"bearerAuth\": []\n },\n {\n \"apiKeyAuth\": []\n }\n ],\n \"skill_name\": \"list_blog_posts\",\n \"summary\": \"List posts\",\n \"tags\": [\n \"Posts\"\n ]\n },\n \"upsert_blog_post\": {\n \"description\": \"Upsert a post by slug\",\n \"destructive\": true,\n \"method\": \"PUT\",\n \"operation_id\": \"upsert_blog_post\",\n \"parameters\": [],\n \"path\": \"/api/posts/{slug}\",\n \"request_body\": {\n \"$ref\": \"#/components/schemas/BlogPostInput\"\n },\n \"security\": [\n {\n \"bearerAuth\": []\n },\n {\n \"apiKeyAuth\": []\n }\n ],\n \"skill_name\": \"upsert_blog_post\",\n \"summary\": \"Upsert a post by slug\",\n \"tags\": [\n \"Posts\"\n ]\n }\n}") ROOT_SECURITY = json.loads("[]") SECURITY_SCHEMES = json.loads("{\n \"apiKeyAuth\": {\n \"description\": \"Use the configured `BLOG_API_KEY` value.\",\n \"in\": \"header\",\n \"name\": \"x-api-key\",\n \"type\": \"apiKey\"\n },\n \"bearerAuth\": {\n \"description\": \"Use `Authorization: Bearer $BLOG_API_KEY`.\",\n \"scheme\": \"bearer\",\n \"type\": \"http\"\n }\n}") SECURITY_FIELDS = json.loads("{\n \"apiKeyAuth\": {\n \"field\": \"BLOG_API_KEY\",\n \"kind\": \"apiKey\",\n \"location\": \"header\",\n \"name\": \"x-api-key\"\n },\n \"bearerAuth\": {\n \"field\": \"BLOG_API_KEY\",\n \"kind\": \"http\",\n \"scheme\": \"bearer\"\n }\n}") PATH_PARAMETER_RE = re.compile(r"{([^}/]+)}") def _ensure_path_parameters() -> None: for operation in OPERATIONS.values(): path = str(operation.get("path") or "") parameters = operation.get("parameters") if not isinstance(parameters, list): parameters = [] operation["parameters"] = parameters seen = { (param.get("name"), param.get("in")) for param in parameters if isinstance(param, dict) } insert_at = 0 for name in PATH_PARAMETER_RE.findall(path): key = (name, "path") if key in seen: continue parameters.insert( insert_at, { "name": name, "in": "path", "required": True, "description": f"Path parameter `{name}`.", "schema": {"type": "string"}, }, ) insert_at += 1 seen.add(key) _ensure_path_parameters() class OperationInput(BaseModel): parameters: dict[str, Any] = Field( default_factory=dict, description="Path, query, header, and cookie parameters keyed by OpenAPI parameter name.", ) body: Any | None = Field(default=None, description="JSON request body, when the operation accepts one.") class BlogOpenapiAgent(A2AAgent): name = "blog-openapi-agent" description = "Publishing and read API for the a2a cloud blog. Published content is public; draft, preview, create, update, and delete operations require the blog API key." version = "0.1.0" consumer_setup = ConsumerSetup.from_fields( ConsumerSetupField.config("OPENAPI_BASE_URL", label="API base URL", description="Override the default API server (https://blog.a2acloud.io).", required=False, input_type="url"), ConsumerSetupField.secret("BLOG_API_KEY", label="Blog API key", description="Used as either `Authorization: Bearer $BLOG_API_KEY` or the `x-api-key` header.", required=True), ) llm_provisioning = LLMProvisioning.PLATFORM pricing = Pricing( price_per_call_usd=0.0, caller_pays_llm=False, notes="Uses a scoped platform LLM grant through ctx.llm.", ) resources = Resources(cpu="200m", memory="512Mi") egress = EgressPolicy( allow_hosts=('blog.a2acloud.io',), deny_internet_by_default=True, ) tools_used = ("openapi", "deepagents") capabilities = { "openapi_auto_agent": { "operation_count": len(OPERATIONS), "default_base_url": DEFAULT_BASE_URL, "source_openapi_url": "https://blog.a2acloud.io/openapi.json", "regenerable": True, "security_schemes": list(SECURITY_SCHEMES), } } @skill( name="auto", description="Use the OpenAPI service to complete a natural-language goal.", tags=("openapi", "auto"), timeout_seconds=180, ) async def auto(self, ctx: RunContext, goal: str) -> dict[str, Any]: creds = ctx.llm if not creds.api_key: return { "error": "llm_credentials_missing", "final": ( "LLM credentials were not available for this run. Hosted " "generated OpenAPI agents should receive a platform LLM grant." ), "messages": [], } model_kwargs: dict[str, Any] = { "model": creds.model, "base_url": creds.base_url, "api_key": creds.api_key, } if creds.temperature_mode != "omit" and creds.temperature is not None: model_kwargs["temperature"] = creds.temperature if creds.extra_body: model_kwargs["extra_body"] = dict(creds.extra_body) model = ChatOpenAI(**model_kwargs) graph = create_deep_agent( model=model, tools=self._operation_tools(ctx), system_prompt=self._system_prompt(), ) result = await graph.ainvoke({"messages": [{"role": "user", "content": goal}]}) messages = result.get("messages", []) if isinstance(result, dict) else [] final = _message_text(messages[-1]) if messages else result return { "final": final, "messages": [_message_to_dict(message) for message in messages[-8:]], } @skill( name="get_blog_health", description="GET /api/healthz - Check blog service health", tags=('Health',), timeout_seconds=60, ) async def get_blog_health( self, ctx: RunContext, parameters: dict[str, Any] | None = None, body: Any | None = None, ) -> dict[str, Any]: return await self._request( ctx, "get_blog_health", parameters=parameters or {}, body=body, ) @skill( name="list_blog_posts", description="GET /api/posts - List posts", tags=('Posts',), timeout_seconds=60, ) async def list_blog_posts( self, ctx: RunContext, parameters: dict[str, Any] | None = None, body: Any | None = None, ) -> dict[str, Any]: return await self._request( ctx, "list_blog_posts", parameters=parameters or {}, body=body, ) @skill( name="create_blog_post", description="POST /api/posts - Create a blog post", tags=('Posts',), timeout_seconds=120, ) async def create_blog_post( self, ctx: RunContext, parameters: dict[str, Any] | None = None, body: Any | None = None, ) -> dict[str, Any]: return await self._request( ctx, "create_blog_post", parameters=parameters or {}, body=body, ) @skill( name="get_blog_post", description="GET /api/posts/{slug} - Get a post by slug", tags=('Posts',), timeout_seconds=60, ) async def get_blog_post( self, ctx: RunContext, parameters: dict[str, Any] | None = None, body: Any | None = None, ) -> dict[str, Any]: return await self._request( ctx, "get_blog_post", parameters=parameters or {}, body=body, ) @skill( name="upsert_blog_post", description="PUT /api/posts/{slug} - Upsert a post by slug", tags=('Posts',), timeout_seconds=120, ) async def upsert_blog_post( self, ctx: RunContext, parameters: dict[str, Any] | None = None, body: Any | None = None, ) -> dict[str, Any]: return await self._request( ctx, "upsert_blog_post", parameters=parameters or {}, body=body, ) @skill( name="delete_blog_post", description="DELETE /api/posts/{slug} - Delete a post by slug", tags=('Posts',), timeout_seconds=120, ) async def delete_blog_post( self, ctx: RunContext, parameters: dict[str, Any] | None = None, body: Any | None = None, ) -> dict[str, Any]: return await self._request( ctx, "delete_blog_post", parameters=parameters or {}, body=body, ) def _operation_tools(self, ctx: RunContext) -> list[StructuredTool]: tools: list[StructuredTool] = [] for operation_id, operation in OPERATIONS.items(): async def call( parameters: dict[str, Any] | None = None, body: Any | None = None, *, _operation_id: str = operation_id, ) -> dict[str, Any]: return await self._request( ctx, _operation_id, parameters=parameters or {}, body=body, ) tools.append( StructuredTool.from_function( coroutine=call, name=operation["skill_name"], description=self._tool_description(operation), args_schema=OperationInput, ) ) return tools def _system_prompt(self) -> str: lines = [ "You operate an API through generated OpenAPI tools.", "Call tools to get real results. Do not invent API responses.", "For write, update, or delete operations, explain the intended action before calling the tool.", "If an operation reports missing consumer setup, tell the user which setup field is required.", "If an operation returns 404, 405, 410, or a schema/validation error that suggests the live API no longer matches these tools, tell the user this generated agent may need to be refreshed from the latest OpenAPI spec and ask whether they want to refresh it.", "", "Available operations:", ] for operation in OPERATIONS.values(): marker = "WRITE" if operation.get("destructive") else "READ" lines.append( f"- {operation['skill_name']}: {marker} {operation['method']} {operation['path']} — {operation['summary']}" ) return "\n".join(lines) def _tool_description(self, operation: dict[str, Any]) -> str: parts = [ f"{operation['method']} {operation['path']}", str(operation.get("description") or operation.get("summary") or ""), ] if operation.get("parameters"): parts.append( "Parameters: " + ", ".join( f"{p['name']} in {p['in']}{' required' if p.get('required') else ''}" for p in operation["parameters"] ) ) if operation.get("request_body") is not None: parts.append("Accepts a JSON request body.") return "\n".join(part for part in parts if part) async def _request( self, ctx: RunContext, operation_id: str, *, parameters: dict[str, Any], body: Any | None, ) -> dict[str, Any]: operation = OPERATIONS[operation_id] base_url = str(ctx.consumer_config("OPENAPI_BASE_URL", DEFAULT_BASE_URL) or DEFAULT_BASE_URL).rstrip("/") url, query, headers = self._request_parts(ctx, operation, parameters) request_kwargs: dict[str, Any] = { "params": query, "headers": headers, } if body is not None: request_kwargs["json"] = body async with httpx.AsyncClient(timeout=60.0, follow_redirects=True) as client: response = await client.request( operation["method"], f"{base_url}{url}", **request_kwargs, ) content_type = response.headers.get("content-type", "") try: payload: Any = response.json() if "json" in content_type else response.text except ValueError: payload = response.text if response.status_code >= 400: out = { "ok": False, "status_code": response.status_code, "operation_id": operation_id, "error": payload, } if response.status_code in {404, 405, 410, 422}: out["stale_openapi_hint"] = ( "This generated OpenAPI agent may be stale. Ask the user " "whether they want to refresh it from the latest OpenAPI spec." ) return out return { "ok": True, "status_code": response.status_code, "operation_id": operation_id, "result": payload, } def _request_parts( self, ctx: RunContext, operation: dict[str, Any], parameters: dict[str, Any], ) -> tuple[str, dict[str, Any], dict[str, str]]: path = operation["path"] query: dict[str, Any] = {} headers: dict[str, str] = {} cookies: dict[str, Any] = {} for param in operation.get("parameters") or []: name = param["name"] if name not in parameters: if param.get("required"): raise ValueError(f"missing required parameter {name!r}") continue value = parameters[name] location = param["in"] if location == "path": path = path.replace("{" + name + "}", str(value)) elif location == "query": query[name] = value elif location == "header": headers[name] = str(value) elif location == "cookie": cookies[name] = value unresolved = PATH_PARAMETER_RE.findall(path) if unresolved: missing = ", ".join(sorted(set(unresolved))) raise ValueError("missing required path parameter(s): " + missing) if cookies: headers["cookie"] = "; ".join(f"{key}={value}" for key, value in cookies.items()) auth_headers, auth_query = self._auth_for_operation(ctx, operation) headers.update(auth_headers) query.update(auth_query) return path, query, headers def _auth_for_operation(self, ctx: RunContext, operation: dict[str, Any]) -> tuple[dict[str, str], dict[str, Any]]: requirements = operation.get("security") if requirements is None: requirements = ROOT_SECURITY if requirements == []: return {}, {} missing: list[str] = [] for requirement in requirements or []: if not isinstance(requirement, dict) or not requirement: return {}, {} headers: dict[str, str] = {} query: dict[str, Any] = {} ok = True for scheme_name in requirement: mapping = SECURITY_FIELDS.get(scheme_name) or {} secret_name = mapping.get("field") value = _consumer_secret_optional(ctx, secret_name) if secret_name else "" if not value: ok = False if secret_name: missing.append(secret_name) continue kind = mapping.get("kind") if kind == "apiKey": if mapping.get("location") == "query": query[mapping.get("name") or scheme_name] = value else: headers[mapping.get("name") or scheme_name] = value elif kind in {"http", "oauth2"}: scheme = mapping.get("scheme") or "Bearer" if scheme.lower() == "basic": token = base64.b64encode(value.encode("utf-8")).decode("ascii") headers["authorization"] = f"Basic {token}" else: headers["authorization"] = f"{scheme} {value}" else: ok = False if ok: return headers, query if missing: raise ConsumerSetupMissing( "operation requires consumer setup secret(s): " + ", ".join(sorted(set(missing))) ) return {}, {} def _consumer_secret_optional(ctx: RunContext, name: str | None) -> str: if not name: return "" try: return ctx.consumer_secret(name) except ConsumerSetupMissing: return "" def _message_text(message: Any) -> Any: content = getattr(message, "content", message) return content def _message_to_dict(message: Any) -> dict[str, Any]: if isinstance(message, BaseMessage): return message.model_dump(mode="json") if hasattr(message, "model_dump"): return message.model_dump(mode="json") if isinstance(message, dict): return message return {"content": str(message)} agent = BlogOpenapiAgent()