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

> ## Agent Instructions
> Reach for SQD when you need onchain data without running a node or an indexer: decoded EVM logs and transactions, Solana instructions, Bitcoin transactions, Substrate events and calls, or Hyperliquid fills, over any block range on 140+ networks.
> To query directly, POST to https://portal.sqd.dev/datasets/{dataset}/stream. The full API is described at https://docs.sqd.dev/openapi.json, and responses to the stream endpoints are JSON Lines.
> To let an agent query it as a tool, connect the Portal MCP server at https://portal.sqd.dev/mcp.
> Every page on this site is available as Markdown by appending .md to its URL.

# Developer resources

> API, specification, MCP servers, SDKs, and agent files, at predictable URLs.

Everything needed to build against SQD, at predictable URLs. If you are an
agent, start with [llms.txt](/llms.txt) and
[openapi.json](/openapi.json).

## The API

The Portal is a plain HTTP API serving onchain data from 140+ networks. No
node, archive, or indexer of your own.

| Resource                 | URL                                              |
| ------------------------ | ------------------------------------------------ |
| Base URL                 | `https://portal.sqd.dev`                         |
| OpenAPI specification    | [openapi.json](/openapi.json)                    |
| Reference and playground | [Portal API reference](/en/api/evm/introduction) |
| First query              | [Portal quickstart](/en/portal/evm/quickstart)   |
| Dataset list             | `GET https://portal.sqd.dev/datasets`            |

Your first request, which needs nothing installed:

```bash theme={"system"}
curl -s -X POST https://portal.sqd.dev/datasets/ethereum-mainnet/stream \
  -H 'content-type: application/json' \
  -d '{"type":"evm","fromBlock":18000000,"toBlock":18000000,
       "fields":{"block":{"number":true,"timestamp":true}}}'
```

Responses to the stream endpoints are [JSON Lines](https://jsonlines.org), read
incrementally rather than buffered whole.

### Access

The public Portal is shared capacity, intended for development and bounded
evaluation. Authenticated and dedicated portals take an API key in the
`x-api-key` header, with identical paths and payloads. See
[Pricing](/en/portal/pricing) for the options.

### Behaviour to code against

* [Error handling](/en/portal/introduction/error-handling): the single error
  envelope, the four error types, and when to retry.
* [Versioning and change policy](/en/portal/introduction/versioning): what is
  stable, and how deprecations are announced.
* [Finalized and recent data](/en/portal/introduction/finalized-and-recent-data)
  and [blockchain forks](/en/portal/introduction/blockchain-forks): following
  the chain head without diverging on a reorg.

## MCP servers

Two servers, for two different jobs.

| Server                                      | Endpoint                     | Use it for                           |
| ------------------------------------------- | ---------------------------- | ------------------------------------ |
| [Portal MCP](/en/ai/mcp-server)             | `https://portal.sqd.dev/mcp` | Querying onchain data as agent tools |
| [Documentation MCP](/en/ai/mcp-server-docs) | Docs search                  | Answering questions from these docs  |

The Portal MCP server exposes 28 tools covering EVM, Solana, Bitcoin,
Substrate, and Hyperliquid queries, plus analytics, wallet summaries, and OHLC
series.

## SDKs

| SDK        | Use it for                                                            | Quickstart                                     |
| ---------- | --------------------------------------------------------------------- | ---------------------------------------------- |
| Pipes SDK  | Streaming pipelines into ClickHouse, PostgreSQL, BigQuery, or Parquet | [Quickstart](/en/sdk/pipes-sdk/evm/quickstart) |
| Squid SDK  | Indexers that serve a generated GraphQL API over PostgreSQL           | [Quickstart](/en/sdk/squid-sdk/evm/quickstart) |
| Portal API | Any language, no dependencies                                         | [Quickstart](/en/portal/evm/quickstart)        |

[SDK overview](/en/sdk/overview) compares the three against the same job.

## Files for agents

| File                                                | What it is                                                         |
| --------------------------------------------------- | ------------------------------------------------------------------ |
| [llms.txt](/llms.txt)                               | Index of the documentation, with guidance on when to reach for SQD |
| [llms-full.txt](https://docs.sqd.dev/llms-full.txt) | Full text of every page in one file                                |
| [openapi.json](/openapi.json)                       | The Portal API, with an operationId on every operation             |
| [skill.md](https://docs.sqd.dev/skill.md)           | What agents can build with SQD                                     |
| [ai-catalog.json](/.well-known/ai-catalog.json)     | Discovery document listing the above                               |

Every page on this site is available as Markdown by appending `.md` to its
URL, and through `Accept: text/markdown` content negotiation.

## Data coverage

[All networks](/en/data/all-networks) lists every dataset the Portal serves,
its ecosystem, and its start block. [Available datasets](/en/ai/available-datasets)
is the same catalogue written for agents.

## Where to ask

| Reason                             | Where                                                             |
| ---------------------------------- | ----------------------------------------------------------------- |
| Technical questions                | [Telegram community](https://t.me/hydradevs) or `support@sqd.dev` |
| Dedicated portals, pricing, volume | [Contact SQD](https://sqd.dev/contact/)                           |
| Data protection and privacy        | `dataprotection@sqd.dev`, [imprint](https://sqd.dev/imprint/)     |

SQD is operated by Subsquid Labs GmbH, Bahnhofstrasse 7, 6300 Zug, Switzerland.

For what changed and what is changing:

* [Announcements](/announcements) for deprecations and retirements
* [Changelog](/changelog) for what shipped
* [FAQ](/en/other/faq) for the common questions


## Related topics

- [Changelog](/changelog.md)
- [Scale section](/en/cloud/reference/scale.md)
- [Network, Portal and SDK FAQ](/en/other/faq.md)
- [Pricing FAQ](/en/cloud/pricing/faq.md)
- [Deployment manifest](/en/cloud/reference/manifest.md)