# Start with Sponge

Write your first cited note in the editor, then make your first call to the agent API.

Docs edition 2026.09. Reviewed 2 September 2026.

## Write your first cited note

Create a private document, write a paragraph, and attach one exact piece of evidence to it.

1. Sign in with your Hraness account.
2. Open /new to create a private document.
3. Write the question, then one sentence you believe is true about it.
4. Open the citation evidence picker at the end of the sentence.
5. Choose the source and state its bearing (supports, contradicts, corroborates, quotes, reports a method, or background).
6. Check the Sources list for the title, publication year, and evidence kind.
7. Choose Export… for portable Markdown with a loss report, or a lossless recovery copy.

## Make your first API call

Create a token, confirm it, create one private document, and read its revision from your own agent.

Sign in and open /settings/api to create a token. Account-wide access is needed only to create the first document; a document-bound token covers later work.

1. Create an account-wide token on the Agent access page, then export it. Tokens are short-lived.

```sh
export SPONGE_API_TOKEN="paste-the-token-here"
```

2. Confirm the token and its remaining request budget.

```sh
curl -s https://sponge.computer/api/v1/auth \
  -H "Authorization: Bearer $SPONGE_API_TOKEN"
```

3. Create one private document. The response body carries its opaque documentRef.

```sh
curl -s https://sponge.computer/api/v1/documents \
  -H "Authorization: Bearer $SPONGE_API_TOKEN" \
  -H "Content-Type: application/json" \
  -H "Idempotency-Key: first-doc-$(date +%s)" \
  -d '{"v":1,"title":"How should this question be investigated?"}'
```

4. Read the document and keep the Sponge-Revision header; every later write sends it back as Sponge-If-Revision.

```sh
curl -si https://sponge.computer/api/v1/documents/sdoc_YOUR_DOCUMENT_REF \
  -H "Authorization: Bearer $SPONGE_API_TOKEN" | grep -i '^sponge-revision\|^{'
```

Then read exact state with `Sponge-Revision`, apply a mutation with `Sponge-If-Revision` and a fresh idempotency key (a missing revision returns 428, a stale one 412), delegate a research job when useful, and hand judgment back to a person.

- [Agent manifest](https://sponge.computer/.well-known/sponge-agent.json)
- [OpenAPI 3.1](https://sponge.computer/openapi.json)
- [Sponge research skill](https://sponge.computer/skills/sponge-research/SKILL.md)
- [Sponge developer resources](https://sponge.computer/developer)

## Other docs pages

- [Guides: Sponge guides](https://sponge.computer/docs/guides)
- [Concepts: How Sponge knowledge works](https://sponge.computer/docs)
- [Reference: Sponge reference](https://sponge.computer/docs/reference)
- [Status: Status and limits](https://sponge.computer/docs/status)
- [Sponge developer resources](https://sponge.computer/developer)
- [OpenAPI 3.1](https://sponge.computer/openapi.json)