# OpenAPI to LLM Tools & Function Calling (`awesome_highboy/openapi-llm`) Actor

Convert any OpenAPI/Swagger spec into per-endpoint LLM tool definitions (function calling schemas) plus clean Markdown docs. Generates JSON-schema tools ready for OpenAI, Claude/Anthropic, and any agent framework. Paste a spec URL or inline JSON; deterministic, content-hashed output per endpoint.

- **URL**: https://apify.com/awesome\_highboy/openapi-llm.md
- **Developed by:** [Adam](https://apify.com/awesome_highboy) (community)
- **Categories:** Developer tools, AI, Agents
- **Stats:** 2 total users, 1 monthly users, 100.0% runs succeeded, 0 bookmarks
- **User rating**: No ratings yet

## Pricing

from $1.50 / 1,000 endpoint processeds

This Actor is paid per event. You are not charged for the Apify platform usage, but only a fixed price for specific events.

Learn more: https://docs.apify.com/platform/actors/running/actors-in-store#pay-per-event

## What's an Apify Actor?

Actors are a software tools running on the Apify platform, for all kinds of web data extraction and automation use cases.
In Batch mode, an Actor accepts a well-defined JSON input, performs an action which can take anything from a few seconds to a few hours,
and optionally produces a well-defined JSON output, datasets with results, or files in key-value store.
In Standby mode, an Actor provides a web server which can be used as a website, API, or an MCP server.
Actors are written with capital "A".

## How to integrate an Actor?

If asked about integration, you help developers integrate Actors into their projects.
You adapt to their stack and deliver integrations that are safe, well-documented, and production-ready.
The best way to integrate Actors is as follows.

In JavaScript/TypeScript projects, use official [JavaScript/TypeScript client](https://docs.apify.com/api/client/js.md):

```bash
npm install apify-client
```

In Python projects, use official [Python client library](https://docs.apify.com/api/client/python.md):

```bash
pip install apify-client
```

In shell scripts, use [Apify CLI](https://docs.apify.com/cli/docs.md):

````bash
# MacOS / Linux
curl -fsSL https://apify.com/install-cli.sh | bash
# Windows
irm https://apify.com/install-cli.ps1 | iex
```bash

In AI frameworks, you might use the [Apify MCP server](https://docs.apify.com/platform/integrations/mcp.md).

If your project is in a different language, use the [REST API](https://docs.apify.com/api/v2.md).

For usage examples, see the [API](#api) section below.

For more details, see Apify documentation as [Markdown index](https://docs.apify.com/llms.txt) and [Markdown full-text](https://docs.apify.com/llms-full.txt).


# README

## OpenAPI to LLM Markdown + Tool Defs

Convert an OpenAPI/Swagger spec into clean per-endpoint Markdown docs and ready-to-use agent tool-call definitions.

### What it does

Give the Actor an OpenAPI/Swagger spec (inline JSON or a URL) and it walks every path and HTTP method (`get`, `post`, `put`, `patch`, `delete`, `options`, `head`) in the spec. For each operation it produces two things:

- A clean **Markdown doc** for that endpoint — method, path, operationId, summary, a parameter list (name, type, required flag, description) and the set of response status codes.
- An **agent tool-call definition** — a `name`, a `description`, and a JSON-Schema-style `parameters` object (`type: object`, `properties`, `required`) built from the operation's path/query parameters and its `application/json` request-body fields.

Parameters are collected from both path-level and operation-level `parameters`, plus the JSON request body. When an operation has no `operationId`, a deterministic one is derived from the method and path. When a field has no declared type, it falls back to `string`; when an operation has no summary, the tool description falls back to `METHOD /path`. Descriptions and summaries are passed through from the spec as written — the Actor does not invent or rewrite API semantics.

Every emitted record includes a deterministic `content_hash` (`sha256:<64 hex>`), so identical input always yields identical hashes — convenient for caching, diffing, and idempotent downstream pipelines.

### Input

| Field | Type | Required | Description |
|---|---|---|---|
| `ownership_attestation` | boolean | **Yes** | You confirm you own or are authorized to use this spec. Must be `true` or the run is rejected before any work, with zero billing. |
| `specUrl` | string | No | URL to an OpenAPI/Swagger JSON spec you own or are authorized to use. |
| `spec` | object | No | The OpenAPI spec inline as JSON. |

Provide either `spec` (inline JSON) or `specUrl`. If `spec` is absent, the Actor fetches `specUrl` and parses it as JSON.

### Output

Records are pushed to the dataset. Every record has a `record_type` of `endpoint_doc`, `tool_def`, or `run_summary`.

**`endpoint_doc`** — one per parsed operation:

- `method` — HTTP method, uppercased
- `path` — the path template
- `operationId` — declared or deterministically derived
- `summary` — the operation summary/description from the spec
- `markdown` — the rendered Markdown doc
- `content_hash` — `sha256:` hash of the Markdown

**`tool_def`** — one per generated tool definition:

- `name` — the operationId
- `description` — summary (or `METHOD /path` fallback), capped at 1024 chars
- `parameters` — JSON-Schema-style object (`type`, `properties`, `required`)
- `content_hash` — `sha256:` hash of the parameters

**`run_summary`** — one per run:

- `spec_title`, `spec_version` — pulled from the spec's `info`
- `endpoints_processed` — number of operations parsed
- `tools_emitted` — number of tool definitions generated

### Pricing

This Actor uses Apify Pay-Per-Event:

| Event | Price (USD) | When it fires |
|---|---|---|
| `actor_run_start` | $0.04 | Once per run, after the gates pass |
| `endpoint_processed` | $0.0015 | Per OpenAPI operation parsed into Markdown |
| `tool_def_emitted` | $0.0008 | Per agent tool-call definition generated |

**Example run cost** — a spec with 40 operations (so 40 endpoint docs and 40 tool defs):

- `actor_run_start`: 1 x $0.04 = $0.04
- `endpoint_processed`: 40 x $0.0015 = $0.06
- `tool_def_emitted`: 40 x $0.0008 = $0.032
- **Total: $0.132**

A run that is rejected at the ownership gate, or that runs on a non-paid plan, is billed **$0.00**.

### Why this Actor

- **Deterministic and idempotent.** Parsing is pure and crypto-only; each record carries a reproducible `sha256` `content_hash`, so re-running the same spec produces byte-identical output and stable hashes for caching and diffing.
- **Ownership attestation gate.** The run is rejected before any processing or billing unless you attest you own or are authorized to use the spec. Default-deny on free plans, too.
- **No invented semantics.** Summaries, descriptions, parameter names and types come straight from your spec. Missing values fall back to safe defaults (`string` type, `METHOD /path` description) rather than being hallucinated.
- **Agent-ready output.** The tool definitions are emitted in the JSON-Schema `{ name, description, parameters }` shape that LLM tool-calling expects, and each endpoint gets its own self-contained Markdown doc.

### About

This Actor is AI-authored and operated under the publisher's LLC. It bills only via `Actor.charge()`, which charges the customer for the Pay-Per-Event events above — the Actor contains no payout or money-out capability of any kind.

# Actor input Schema

## `specUrl` (type: `string`):

URL to an OpenAPI/Swagger JSON spec you own or are authorized to use.
## `spec` (type: `object`):

OpenAPI spec (inline JSON)
## `ownership_attestation` (type: `boolean`):

I own/am authorized to use this spec (REQUIRED)

## Actor input object example

```json
{
  "ownership_attestation": false
}
````

# API

You can run this Actor programmatically using our API. Below are code examples in JavaScript, Python, and CLI, as well as the OpenAPI specification and MCP server setup.

## JavaScript example

```javascript
import { ApifyClient } from 'apify-client';

// Initialize the ApifyClient with your Apify API token
// Replace the '<YOUR_API_TOKEN>' with your token
const client = new ApifyClient({
    token: '<YOUR_API_TOKEN>',
});

// Prepare Actor input
const input = {};

// Run the Actor and wait for it to finish
const run = await client.actor("awesome_highboy/openapi-llm").call(input);

// Fetch and print Actor results from the run's dataset (if any)
console.log('Results from dataset');
console.log(`💾 Check your data here: https://console.apify.com/storage/datasets/${run.defaultDatasetId}`);
const { items } = await client.dataset(run.defaultDatasetId).listItems();
items.forEach((item) => {
    console.dir(item);
});

// 📚 Want to learn more 📖? Go to → https://docs.apify.com/api/client/js/docs

```

## Python example

```python
from apify_client import ApifyClient

# Initialize the ApifyClient with your Apify API token
# Replace '<YOUR_API_TOKEN>' with your token.
client = ApifyClient("<YOUR_API_TOKEN>")

# Prepare the Actor input
run_input = {}

# Run the Actor and wait for it to finish
run = client.actor("awesome_highboy/openapi-llm").call(run_input=run_input)

# Fetch and print Actor results from the run's dataset (if there are any)
print("💾 Check your data here: https://console.apify.com/storage/datasets/" + run["defaultDatasetId"])
for item in client.dataset(run["defaultDatasetId"]).iterate_items():
    print(item)

# 📚 Want to learn more 📖? Go to → https://docs.apify.com/api/client/python/docs/quick-start

```

## CLI example

```bash
echo '{}' |
apify call awesome_highboy/openapi-llm --silent --output-dataset

```

## MCP server setup

```json
{
    "mcpServers": {
        "apify": {
            "command": "npx",
            "args": [
                "mcp-remote",
                "https://mcp.apify.com/?tools=awesome_highboy/openapi-llm",
                "--header",
                "Authorization: Bearer <YOUR_API_TOKEN>"
            ]
        }
    }
}

```

## OpenAPI specification

```json
{
    "openapi": "3.0.1",
    "info": {
        "title": "OpenAPI to LLM Tools & Function Calling",
        "description": "Convert any OpenAPI/Swagger spec into per-endpoint LLM tool definitions (function calling schemas) plus clean Markdown docs. Generates JSON-schema tools ready for OpenAI, Claude/Anthropic, and any agent framework. Paste a spec URL or inline JSON; deterministic, content-hashed output per endpoint.",
        "version": "0.1",
        "x-build-id": "BgCpXK1i7DnmUr3ZP"
    },
    "servers": [
        {
            "url": "https://api.apify.com/v2"
        }
    ],
    "paths": {
        "/acts/awesome_highboy~openapi-llm/run-sync-get-dataset-items": {
            "post": {
                "operationId": "run-sync-get-dataset-items-awesome_highboy-openapi-llm",
                "x-openai-isConsequential": false,
                "summary": "Executes an Actor, waits for its completion, and returns Actor's dataset items in response.",
                "tags": [
                    "Run Actor"
                ],
                "requestBody": {
                    "required": true,
                    "content": {
                        "application/json": {
                            "schema": {
                                "$ref": "#/components/schemas/inputSchema"
                            }
                        }
                    }
                },
                "parameters": [
                    {
                        "name": "token",
                        "in": "query",
                        "required": true,
                        "schema": {
                            "type": "string"
                        },
                        "description": "Enter your Apify token here"
                    }
                ],
                "responses": {
                    "200": {
                        "description": "OK"
                    }
                }
            }
        },
        "/acts/awesome_highboy~openapi-llm/runs": {
            "post": {
                "operationId": "runs-sync-awesome_highboy-openapi-llm",
                "x-openai-isConsequential": false,
                "summary": "Executes an Actor and returns information about the initiated run in response.",
                "tags": [
                    "Run Actor"
                ],
                "requestBody": {
                    "required": true,
                    "content": {
                        "application/json": {
                            "schema": {
                                "$ref": "#/components/schemas/inputSchema"
                            }
                        }
                    }
                },
                "parameters": [
                    {
                        "name": "token",
                        "in": "query",
                        "required": true,
                        "schema": {
                            "type": "string"
                        },
                        "description": "Enter your Apify token here"
                    }
                ],
                "responses": {
                    "200": {
                        "description": "OK",
                        "content": {
                            "application/json": {
                                "schema": {
                                    "$ref": "#/components/schemas/runsResponseSchema"
                                }
                            }
                        }
                    }
                }
            }
        },
        "/acts/awesome_highboy~openapi-llm/run-sync": {
            "post": {
                "operationId": "run-sync-awesome_highboy-openapi-llm",
                "x-openai-isConsequential": false,
                "summary": "Executes an Actor, waits for completion, and returns the OUTPUT from Key-value store in response.",
                "tags": [
                    "Run Actor"
                ],
                "requestBody": {
                    "required": true,
                    "content": {
                        "application/json": {
                            "schema": {
                                "$ref": "#/components/schemas/inputSchema"
                            }
                        }
                    }
                },
                "parameters": [
                    {
                        "name": "token",
                        "in": "query",
                        "required": true,
                        "schema": {
                            "type": "string"
                        },
                        "description": "Enter your Apify token here"
                    }
                ],
                "responses": {
                    "200": {
                        "description": "OK"
                    }
                }
            }
        }
    },
    "components": {
        "schemas": {
            "inputSchema": {
                "type": "object",
                "required": [
                    "ownership_attestation"
                ],
                "properties": {
                    "specUrl": {
                        "title": "OpenAPI spec URL",
                        "type": "string",
                        "description": "URL to an OpenAPI/Swagger JSON spec you own or are authorized to use."
                    },
                    "spec": {
                        "title": "OpenAPI spec (inline JSON)",
                        "type": "object",
                        "description": "OpenAPI spec (inline JSON)"
                    },
                    "ownership_attestation": {
                        "title": "I own/am authorized to use this spec (REQUIRED)",
                        "type": "boolean",
                        "description": "I own/am authorized to use this spec (REQUIRED)",
                        "default": false
                    }
                }
            },
            "runsResponseSchema": {
                "type": "object",
                "properties": {
                    "data": {
                        "type": "object",
                        "properties": {
                            "id": {
                                "type": "string"
                            },
                            "actId": {
                                "type": "string"
                            },
                            "userId": {
                                "type": "string"
                            },
                            "startedAt": {
                                "type": "string",
                                "format": "date-time",
                                "example": "2025-01-08T00:00:00.000Z"
                            },
                            "finishedAt": {
                                "type": "string",
                                "format": "date-time",
                                "example": "2025-01-08T00:00:00.000Z"
                            },
                            "status": {
                                "type": "string",
                                "example": "READY"
                            },
                            "meta": {
                                "type": "object",
                                "properties": {
                                    "origin": {
                                        "type": "string",
                                        "example": "API"
                                    },
                                    "userAgent": {
                                        "type": "string"
                                    }
                                }
                            },
                            "stats": {
                                "type": "object",
                                "properties": {
                                    "inputBodyLen": {
                                        "type": "integer",
                                        "example": 2000
                                    },
                                    "rebootCount": {
                                        "type": "integer",
                                        "example": 0
                                    },
                                    "restartCount": {
                                        "type": "integer",
                                        "example": 0
                                    },
                                    "resurrectCount": {
                                        "type": "integer",
                                        "example": 0
                                    },
                                    "computeUnits": {
                                        "type": "integer",
                                        "example": 0
                                    }
                                }
                            },
                            "options": {
                                "type": "object",
                                "properties": {
                                    "build": {
                                        "type": "string",
                                        "example": "latest"
                                    },
                                    "timeoutSecs": {
                                        "type": "integer",
                                        "example": 300
                                    },
                                    "memoryMbytes": {
                                        "type": "integer",
                                        "example": 1024
                                    },
                                    "diskMbytes": {
                                        "type": "integer",
                                        "example": 2048
                                    }
                                }
                            },
                            "buildId": {
                                "type": "string"
                            },
                            "defaultKeyValueStoreId": {
                                "type": "string"
                            },
                            "defaultDatasetId": {
                                "type": "string"
                            },
                            "defaultRequestQueueId": {
                                "type": "string"
                            },
                            "buildNumber": {
                                "type": "string",
                                "example": "1.0.0"
                            },
                            "containerUrl": {
                                "type": "string"
                            },
                            "usage": {
                                "type": "object",
                                "properties": {
                                    "ACTOR_COMPUTE_UNITS": {
                                        "type": "integer",
                                        "example": 0
                                    },
                                    "DATASET_READS": {
                                        "type": "integer",
                                        "example": 0
                                    },
                                    "DATASET_WRITES": {
                                        "type": "integer",
                                        "example": 0
                                    },
                                    "KEY_VALUE_STORE_READS": {
                                        "type": "integer",
                                        "example": 0
                                    },
                                    "KEY_VALUE_STORE_WRITES": {
                                        "type": "integer",
                                        "example": 1
                                    },
                                    "KEY_VALUE_STORE_LISTS": {
                                        "type": "integer",
                                        "example": 0
                                    },
                                    "REQUEST_QUEUE_READS": {
                                        "type": "integer",
                                        "example": 0
                                    },
                                    "REQUEST_QUEUE_WRITES": {
                                        "type": "integer",
                                        "example": 0
                                    },
                                    "DATA_TRANSFER_INTERNAL_GBYTES": {
                                        "type": "integer",
                                        "example": 0
                                    },
                                    "DATA_TRANSFER_EXTERNAL_GBYTES": {
                                        "type": "integer",
                                        "example": 0
                                    },
                                    "PROXY_RESIDENTIAL_TRANSFER_GBYTES": {
                                        "type": "integer",
                                        "example": 0
                                    },
                                    "PROXY_SERPS": {
                                        "type": "integer",
                                        "example": 0
                                    }
                                }
                            },
                            "usageTotalUsd": {
                                "type": "number",
                                "example": 0.00005
                            },
                            "usageUsd": {
                                "type": "object",
                                "properties": {
                                    "ACTOR_COMPUTE_UNITS": {
                                        "type": "integer",
                                        "example": 0
                                    },
                                    "DATASET_READS": {
                                        "type": "integer",
                                        "example": 0
                                    },
                                    "DATASET_WRITES": {
                                        "type": "integer",
                                        "example": 0
                                    },
                                    "KEY_VALUE_STORE_READS": {
                                        "type": "integer",
                                        "example": 0
                                    },
                                    "KEY_VALUE_STORE_WRITES": {
                                        "type": "number",
                                        "example": 0.00005
                                    },
                                    "KEY_VALUE_STORE_LISTS": {
                                        "type": "integer",
                                        "example": 0
                                    },
                                    "REQUEST_QUEUE_READS": {
                                        "type": "integer",
                                        "example": 0
                                    },
                                    "REQUEST_QUEUE_WRITES": {
                                        "type": "integer",
                                        "example": 0
                                    },
                                    "DATA_TRANSFER_INTERNAL_GBYTES": {
                                        "type": "integer",
                                        "example": 0
                                    },
                                    "DATA_TRANSFER_EXTERNAL_GBYTES": {
                                        "type": "integer",
                                        "example": 0
                                    },
                                    "PROXY_RESIDENTIAL_TRANSFER_GBYTES": {
                                        "type": "integer",
                                        "example": 0
                                    },
                                    "PROXY_SERPS": {
                                        "type": "integer",
                                        "example": 0
                                    }
                                }
                            }
                        }
                    }
                }
            }
        }
    }
}
```