Bittensor's subtensor chain is a Substrate chain, producing a finalized block roughly every 12 seconds. Each block has a header (a parent hash linking it to the one before, plus a state root and extrinsics root committing to what changed) and a body — the ordered extrinsics it carried. This page covers the block-level surface everything else (extrinsics, chain events, account activity) is anchored to.

```
GET https://api.metagraph.sh/api/v1/blocks
```

## GET /api/v1/blocks [#get-apiv1blocks]

Recent-block feed, newest first.

| Param                           | Notes                                                                 |
| ------------------------------- | --------------------------------------------------------------------- |
| `limit`                         | 1–100, default 50.                                                    |
| `offset` / `cursor`             | Offset or keyset paging. Out-of-range values clamp rather than error. |
| `author`                        | Scope to one block-authoring validator.                               |
| `spec_version`                  | Scope to one runtime spec version.                                    |
| `block_start` / `block_end`     | Block-number range.                                                   |
| `from` / `to`                   | Epoch-ms observed-at range.                                           |
| `min_extrinsics` / `min_events` | Floor filters — numeric input, 400s on non-integer.                   |
| `format`                        | `csv`.                                                                |

```bash
curl -s 'https://api.metagraph.sh/api/v1/blocks?min_extrinsics=5&limit=10'
```

## GET /api/v1/blocks/\{ref} [#get-apiv1blocksref]

One block's header — `{ref}` accepts either a decimal block number or a `0x` + 64-hex block hash. An unknown block never 404s: it returns `{ block: null }` with a 200. The response includes the nearest stored `prev`/`next_block_number` for chain-walk navigation.

```bash
curl -s https://api.metagraph.sh/api/v1/blocks/5000000
```

## Extrinsics & events in one block [#extrinsics--events-in-one-block]

| Path                                    | Returns                                                                                                   | Params                                    |
| --------------------------------------- | --------------------------------------------------------------------------------------------------------- | ----------------------------------------- |
| `GET /api/v1/blocks/{ref}/extrinsics`   | The extrinsics in this block, index-ascending.                                                            | `limit` (≤100), `offset`, `format=csv`    |
| `GET /api/v1/blocks/{ref}/events`       | Curated, account-attributed events (a fixed allowlist of "interesting" kinds).                            | `limit` (≤1000), `offset`, `format=csv`   |
| `GET /api/v1/blocks/{ref}/chain-events` | **Every** raw `pallet.method` event in this block, unfiltered — no limit/offset, returns the whole block. | numeric `block_number` only, no hash form |

<Callout title="chain-events is a proxy with its own rate limit">
  `/blocks/{ref}/chain-events` forwards to a separate deep-history Worker over a service binding,
  the same tier documented in full on the [chain events reference](/docs/chain-events) — including
  its own 60 req/60s rate limiter and the 503 you'll get if that binding isn't wired into a
  deployment. See that page rather than duplicating it here.
</Callout>

## Block-production analytics & runtime versions [#block-production-analytics--runtime-versions]

| Path                         | Purpose                                                                                                     |
| ---------------------------- | ----------------------------------------------------------------------------------------------------------- |
| `GET /api/v1/blocks/summary` | Inter-block timing, throughput, author decentralization, spec-version spread.                               |
| `GET /api/v1/runtime`        | The runtime spec-version transition timeline — every distinct `spec_version` seen, earliest block for each. |

`/api/v1/runtime` reports only `spec_version` (not the full Substrate `RuntimeVersion` struct), read directly off each block's own `spec_version` column — that column only started being captured from a fixed point on, so `coverage_from_block`/`coverage_from_at` mark where the recorded history actually begins. It's grouped with Blocks rather than a general "chain" surface because it's a pure aggregate over the same block-header data `/blocks/summary`'s `latest_spec_version` field also derives from.

<Callout title="current_spec_version isn't just the last transition">
  Grouping by spec version collapses each one to its *earliest* block — so if a version were ever
  superseded and then reappeared, naively reading the last transition would report the wrong one as
  current. `current_spec_version` is computed as a separate query instead.
</Callout>

<CodeBlockTabs defaultValue="JavaScript">
  <CodeBlockTabsList>
    <CodeBlockTabsTrigger value="JavaScript">
      JavaScript
    </CodeBlockTabsTrigger>

    <CodeBlockTabsTrigger value="Python">
      Python
    </CodeBlockTabsTrigger>
  </CodeBlockTabsList>

  <CodeBlockTab value="JavaScript">
    ```js
    const res = await fetch("https://api.metagraph.sh/api/v1/blocks/summary");
    const { data } = await res.json();
    ```
  </CodeBlockTab>

  <CodeBlockTab value="Python">
    ```python
    import requests

    data = requests.get("https://api.metagraph.sh/api/v1/blocks/summary").json()["data"]
    ```
  </CodeBlockTab>
</CodeBlockTabs>

`/blocks/{ref}` caches 600s once resolved (finalized blocks are immutable) and 60s while unknown; every other route here caches 60s.

<ApiSources
  paths="[
  &#x22;/api/v1/blocks&#x22;,
  &#x22;/api/v1/blocks/summary&#x22;,
  &#x22;/api/v1/blocks/{ref}&#x22;,
  &#x22;/api/v1/blocks/{ref}/extrinsics&#x22;,
  &#x22;/api/v1/blocks/{ref}/events&#x22;,
  &#x22;/api/v1/runtime&#x22;,
]"
/>