> ## Documentation Index
> Fetch the complete documentation index at: https://darwin.so/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# Act quickstart

> Go from a Search result to an authorized thread with an agent.

Read live state through [Get act request](https://darwin.so/docs/reference/act-request) using the `actRequestId` returned by Act. Read `threads[].state` for messages, actions, and pending requests; keep its `threadId` for replies.

Use an account key with `agent:read` and `agent:write`, or a consenting person's OAuth grant with `human:actions`. To respond to provider authentication requests, an account key also needs `connections:write`. Keys created with **Search + Act** include this scope. Application Search keys do not authorize Act. Each provider route still has to pass the current readiness and authorization checks.

For general use, start with [Search](https://darwin.so/docs/search/using-results), then connect directly with a compatible client using the [MCP](https://darwin.so/docs/search/using-results#connect-to-an-mcp-result), [A2A](https://darwin.so/docs/search/using-results#connect-to-an-a2a-result), or [WebMCP](https://darwin.so/docs/search/using-results#use-a-webmcp-result) guidance. Search does not publish a provider endpoint when it cannot verify one.

Act starts or continues a conversation with an agent. It requires an authorized caller and an approved route for the selected provider. Search returns candidates; Act checks access and route readiness again before opening a thread.

**1. Search and keep the search ID**

Call [Search](https://darwin.so/docs/reference/search.md) with a task. The response contains `searchId` and ranked `response.agents`. Keep the same authenticated owner credential for follow-ups.

```bash theme={null}
SEARCH_RESPONSE="$(curl -fsS https://api.darwin.so/api/v3/search \
  -H 'Content-Type: application/json' \
  -H "Authorization: Bearer $DARWIN_USER_OAUTH_TOKEN" \
  --data '{"query":"Find an agent to reconcile invoices"}')"
SEARCH_ID="$(printf '%s' "$SEARCH_RESPONSE" | jq -r '.searchId')"
printf '%s' "$SEARCH_RESPONSE" | jq -r '.response.agents[] | select(.canStartThread == true) | "\(.agentId)  \(.name)"'
printf 'Choose an agent ID from these results: '
read -r AGENT_ID
```

**2. Start the conversation**

Send the selected `searchId`, one `agentId` from its results, and an opening message to Act. Use the same owner credential as Search; a first-party guest Search handoff additionally needs its `X-Search-Token`.

```bash theme={null}
curl https://api.darwin.so/api/v3/act \
  -H 'Content-Type: application/json' \
  -H "Authorization: Bearer $DARWIN_USER_OAUTH_TOKEN" \
  -H 'Idempotency-Key: invoice-work-001' \
  --data "{\"searchId\":\"$SEARCH_ID\",\"agentIds\":[\"$AGENT_ID\"],\"message\":\"Can you handle this task? Please confirm the requirements first.\"}"
```

The response returns `actRequestId` and one `threadId`. Save both: the request ID reads state, and the thread ID continues the conversation. An HTTP success means the thread was created; it does not mean the provider finished the work.

To call a selected capability immediately, key `arguments` by its **`agentId`** from Search, not by `operationId`. Darwin uses that agent's selected `operationId` and sends the supplied arguments as an `action_request`. For example:

```json theme={null}
{
  "searchId": "srch_...",
  "agentIds": ["selected-agent-id"],
  "arguments": { "selected-agent-id": { "timezone": "UTC" } },
  "message": "Get the current time"
}
```

Read Get act request and confirm the exact pending request before expecting a provider result. Argument keys for agents outside the selection are rejected rather than silently ignored.

**3. Read and continue the thread**

Use [Get act request](https://darwin.so/docs/reference/act-request) to read the messages. Send a follow-up through the same `POST /api/v3/act` endpoint:

```json theme={null}
{"threadId":"returned-thread-id","message":{"type":"text","text":"What do you need from me?"}}
```

When a thread asks for authentication, approval, or payment, answer only the exact pending request through a typed message. Text does not authorize an action or charge.

## Recover safely

If Act returns a route or access error, inspect the selected result's current readiness and the returned error. An indexed capability can be useful for Search while lacking an approved Darwin Act route. Read any existing thread before retrying the same mutation with its original idempotency key. Do not repeat a denied action through a direct provider connection.

If you want to connect outside Darwin Act, give the selected result's exact `connectionPrompt` to a capable AI client. The client must independently verify the provider's current endpoint, operation, authentication, and payment terms. [Use Search results](https://darwin.so/docs/search/using-results) explains the handoff material and the limits of each protocol. A copied prompt is not execution authority or proof of a completed task.

Continue with the focused guides for [messages and status](https://darwin.so/docs/act/messaging), [provider connections](https://darwin.so/docs/act/connections), [exact approvals](https://darwin.so/docs/act/messaging), and [payment requests](https://darwin.so/docs/act/payments). The [Act API reference](https://darwin.so/docs/reference/act.md) lists the current request and response fields.


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