# Agent Quickstart

> Pick REST, an SDK, MCP, or an agent skill.

Source page: https://docs.replynodes.com/docs/agent-quickstart

# Agent Quickstart

Choose in this order:

1. **Start keyless.** Call a keyless capability below right away; no account,
   key, or human is needed. Every response carries `X-RateLimit-Remaining`.
2. **Need more, or a keyed route?** When a call returns
   `429 anonymous_limit_reached` or `401`, read `error.next_action` in the body:
   it names the exact call to make, the fields to send, and a `human_message`
   to show your human. In short: `POST /api/agent/signup` with the human's
   email returns a restricted key at once; ask for the 6-digit code from their
   email and `POST /api/agent/verify` with the same key to upgrade it. No
   browser is needed. The full protocol is
   [https://replynodes.com/auth.md](https://replynodes.com/auth.md); the
   [Authentication page](https://docs.replynodes.com/docs/auth) summarizes it.
3. **Have a key?** Use REST with `REPLYNODES_API_KEY`, or connect an
   MCP-capable client to `https://mcp.replynodes.com/mcp` and configure the key
   through the client's secret mechanism.

## Keyless capabilities

| Capability | Tier | Daily anonymous limit |
| --- | --- | ---: |
| url-to-markdown (`GET https://md.replynodes.com/<url>`) | Markdown | 100/day |
| brand-kit (`GET https://brand.replynodes.com/<domain>`) | Tier A | 20/day |
| brand-logo | Tier A | 20/day |
| app-store-api | Tier B | 10/day |
| google-play-api | Tier B | 10/day |
| reddit-api | Tier B | 10/day |
| youtube-api | Tier B | 10/day |
| web-search | Tier B | 10/day |
| web-scraping | Tier B | 10/day |
| company-research | Tier C | 3/day |
| competitor-research | Tier C | 3/day |

Only these listed capabilities have keyless routes; limits are per caller per
UTC day. At the limit, the API returns `429 anonymous_limit_reached` with
`error.next_action` pointing at the key flow.

| Option | Use it when | Source of truth |
| --- | --- | --- |
| REST | You control the HTTP call or tool function | OpenAPI + API Reference |
| SDK | A generated downstream package is available to your team | `sdk-generation/` configs and canonical OpenAPI |
| MCP | Your client can connect to a remote Streamable HTTP server | [MCP guide](https://docs.replynodes.com/docs/mcp) and generated MCP inventories |
| Agent Skill | Your client reads instruction packages | `services/social-data-skills/generated/` |

## REST tool

Expose a function that performs a `GET` against the exact path from the OpenAPI document, adds an `Authorization: Bearer ${REPLYNODES_API_KEY}` header from a secret store, passes only declared parameters, and returns the JSON envelope. Do not let an agent turn a read operation into a write operation.

## SDK path

This repository does not publish SDK implementations. It does contain the pinned generation target list in `sdk-generation/README.md`: TypeScript (`@replynodes/sdk`), Python (`replynodes`), Go (`github.com/replynodes/replynodes-go`), Ruby (`replynodes`), and PHP (`replynodes/replynodes`) are downstream synchronization targets, not packages you can assume are installable from this repo. Verify package availability and the generated client's auth configuration before using one.

## Client choice

Claude Code, Cursor, Codex, VS Code, Hermes, and OpenCode can all use the REST pattern. MCP-capable clients can use [MCP](https://docs.replynodes.com/docs/mcp) with native OAuth or a ReplyNodes API key. For skill-aware clients, install or reference the generated package that matches the provider; the package's `SKILL.md`, `INSTALL.md`, and `references/` files are authoritative. Do not copy stale endpoint lists into prompts.