---
title: "Get Agent Access challenge"
method: GET
path: "/v1/agent-access/challenge"
tags: ["Agent Access"]
---

# Get Agent Access challenge

`GET /v1/agent-access/challenge`

## Request

- Base URL: `https://api.anchorbrowser.io`
- URL: `https://api.anchorbrowser.io/v1/agent-access/challenge`
- Auth: none required

Get a puzzle and token. Follow next and challenge.prompt, then POST /v1/agent-access with token and answer.

## Response `200`

Challenge payload.

- object
  - `challenge` object, required
    - `id` string, required: Challenge instance id.
    - `type` string, required: Challenge type (semantic_logic).
    - `icon` string, required: Display icon for UIs.
    - `title` string, required: Short challenge title.
    - `description` string, required: Short challenge summary.
    - `prompt` string, required: Multi-step puzzle text. Follow the instructions to compute the final integer answer.
    - `timeLimit` number, required: Suggested solve time in seconds.
  - `token` string, required: Opaque challenge token. Pass to POST /v1/agent-access as token. This is not the puzzle answer.
  - `appendix_ref` string
  - `appendix_url` string
  - `instructions` AgentAccessInstructions, required
    - `submit` string, required: After solving the puzzle, call this endpoint with { token, answer }. token is from this response; answer is the final integer as a string.
    - `appendix` string, required: Optional path hint from the challenge response.
    - `api_key_header` string, required: After POST succeeds, send the returned api_key using this request header on authenticated API calls.
    - `optional_identity` string, required: Optional identity_token on the same POST for more credits and an agent_identity_token for later calls.
    - `anonymous_credits` number, required: Credits granted when POST omits identity_token or the token has no verified email.
    - `identity_credits` number, required: Credits granted when POST includes identity_token with a verified email.
  - `next` AgentAccessNextStep
    - `method` 'GET' | 'POST', required: HTTP method for the next call in the Agent Access onboarding flow.
    - `path` string, required: Path on https://api.anchorbrowser.io for the next call. Prepend the method to execute it.
    - `description` string, required: Plain-language instruction for what to do on the next call and what you receive afterward.

## Other responses

- `429`: Too many challenge requests from this source.
- `500`: Challenge generation failed.

## Changes

- **2026-10-16** `b3bfdb98c79e`: 1 info
  - endpoint added

[Operation history](https://skmtc.dev/anchorbrowser/apis/anchorbrowser-api/changes/v1/agent-access/challenge/get.md)

---

[API](https://skmtc.dev/anchorbrowser/apis/anchorbrowser-api.md) - [All operations](https://skmtc.dev/anchorbrowser/apis/anchorbrowser-api/llms.txt) - [OpenAPI document](https://skmtc.dev/anchorbrowser/apis/anchorbrowser-api/revisions/9d755f22df0e?raw)