<!-- Generated by crates/swarmops-cli/src/reference/mcp_page.rs from the code: do not edit. Change the code, then run SWARMOPS_REGEN_REFERENCE=1 with the regen_reference test. -->

# read_tree

Lists one directory at a revision, without a checkout, a page of entries at a time, each file with its size, and with depth the directories below it too; pass a limit of 100 or less and page on with the cursor, since clients limit long tool results.

```yaml
title: "read_tree"
description: "List a directory."
since: "0.1.0"
mutates: false
identity_required: false
cli_command: "swarmops ls"
envelope_op: "read_tree"
request_type: "ReadTreeReq"
annotations: {"destructiveHint":false,"idempotentHint":true,"openWorldHint":false,"readOnlyHint":true}
max_result_chars: null
```

## Input schema

`arguments` is a `ReadTreeReq`: `swarmops schema ReadTreeReq` prints the type. A field the type does not know is ignored.

| Field | Type | Required | Default | Description |
| --- | --- | --- | --- | --- |
| `cursor` | string or null | no |  | Resume a listing: the previous page's `cursor`. Pass it back exactly as returned; do not construct it (cursors are opaque). This page starts after the entry it names. |
| `depth` | integer | no | `1` | How many levels to list: 1 for the directory's own entries, 2 for theirs too, and so on, up to 64 (0 or more than 64 is `E_INVALID_ARG`). |
| `limit` | integer | no | `250` | The most entries to return: at least 1 (0 is `E_INVALID_ARG`). |
| `path` | string or null | no |  | The directory's repository path; omitted for the root. |
| `rev` | string | yes |  | The revision to read at. A revision as the caller wrote it, for the store to resolve: a ref name (`main`, `release/1.2`), a full 64-hex changeset id or a unique prefix of at least 12 hex digits, optionally followed by `~N` for the N-th first-parent ancestor. |

### JSON Schema

As `tools/list` gives it: each `$ref` replaced by its definition, so that it stands alone.

```json
{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "description": "`read_tree` (CLI `ls`): list one directory at a revision, without a checkout, a page at a\ntime; with `depth`, the directories below it too.",
  "properties": {
    "cursor": {
      "description": "Resume a listing: the previous page's `cursor`. Pass it back exactly as returned; do not\nconstruct it (cursors are opaque). This page starts after the entry it names.",
      "type": [
        "string",
        "null"
      ]
    },
    "depth": {
      "default": 1,
      "description": "How many levels to list: 1 for the directory's own entries, 2 for theirs too, and so on, up\nto 64 (0 or more than 64 is `E_INVALID_ARG`).",
      "format": "uint32",
      "maximum": 64,
      "minimum": 1,
      "type": "integer"
    },
    "limit": {
      "default": 250,
      "description": "The most entries to return: at least 1 (0 is `E_INVALID_ARG`).",
      "format": "uint",
      "minimum": 1,
      "type": "integer"
    },
    "path": {
      "description": "The directory's repository path; omitted for the root.",
      "type": [
        "string",
        "null"
      ]
    },
    "rev": {
      "description": "The revision to read at. A revision as the caller wrote it, for the store to resolve: a ref name (`main`,\n`release/1.2`), a full 64-hex changeset id or a unique prefix of at least 12 hex digits,\noptionally followed by `~N` for the N-th first-parent ancestor.",
      "type": "string"
    }
  },
  "required": [
    "rev"
  ],
  "title": "ReadTreeReq",
  "type": "object"
}
```

## Annotations

It only reads the store.

| Annotation | Value | Meaning |
| --- | --- | --- |
| `destructiveHint` | `false` | True: a tool that changes the store may overwrite or delete what is there, not only add to it. |
| `idempotentHint` | `true` | True: calling it again with the same arguments changes nothing more. |
| `openWorldHint` | `false` | True: it reaches beyond a closed set of things. Every tool here stays inside the store. |
| `readOnlyHint` | `true` | True: the tool does not change its environment, the store. |

Its entry in `tools/list` carries no `_meta`.

## CLI command

[`swarmops ls`](../commands/ls.md) runs the same operation and prints the same envelope.

## Examples

### MCP

```json
{
  "id": 9,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {
      "rev": "main"
    },
    "name": "read_tree"
  }
}
```

```json
{
  "id": 9,
  "jsonrpc": "2.0",
  "result": {
    "content": [
      {
        "text": "{\"ok\":true,\"op\":\"read_tree\",\"api\":1,\"result\":{\"entries\":[{\"name\":\"README.md\",\"kind\":\"file\",\"size\":7,\"id\":\"[blob]\"},{\"name\":\"src\",\"kind\":\"dir\",\"id\":\"[id2]\"}],\"truncated\":false},\"meta\":{\"repo\":\"[tmp]/store\",\"elapsed_ms\":\"[elapsed_ms]\",\"resolved\":{\"main\":\"[c1]\"},\"auth\":\"trust\"}}",
        "type": "text"
      }
    ],
    "isError": false,
    "structuredContent": {
      "api": 1,
      "meta": {
        "auth": "trust",
        "elapsed_ms": "[elapsed_ms]",
        "repo": "[tmp]/store",
        "resolved": {
          "main": "[c1]"
        }
      },
      "ok": true,
      "op": "read_tree",
      "result": {
        "entries": [
          {
            "id": "[blob]",
            "kind": "file",
            "name": "README.md",
            "size": 7
          },
          {
            "id": "[id2]",
            "kind": "dir",
            "name": "src"
          }
        ],
        "truncated": false
      }
    }
  }
}
```

The server ran as `swarmops mcp --repo [tmp]/store --as agent/worker-17`, after `initialize`. Recorded by the MCP tests. A name in square brackets, such as `[tmp]` or `[c1]`, stands for what differs from run to run: the test's temporary directory, an id, a time, the version.

## Details

Pass a `limit` of 100 or less and page on with the `cursor` the result gives.
Each file comes with its size; with `depth`, the directories below the one asked for are listed
too.
No checkout is needed: it reads the tree at the revision.

## Return information

A tool result: the envelope, whose `op` is `read_tree`, as `structuredContent` and again as the text of its one `content` block. `isError` is true exactly when the envelope's `ok` is false. On success the envelope's `result` is what [`swarmops ls`](../commands/ls.md#return-information) returns.

## Errors

A failed call is a tool result with `isError: true`; the envelope's `error.code` is one of the [error codes](../errors.md).

- [`E_INVALID_ARG`](../errors.md#e_invalid_arg): arguments that do not fit `ReadTreeReq`, a field named twice among them included, or that break one of the server's own rules.
- [`E_NOT_A_REPO`](../errors.md#e_not_a_repo): the server's store is not there; the server serves on.
- [`E_INTERNAL`](../errors.md#e_internal): the operation panicked, a bug.

Then the errors of the operation, as [`swarmops ls`](../commands/ls.md#errors) lists them.

## See also

- [`swarmops ls`](../commands/ls.md)
- [MCP tools](README.md)
- [MCP integration](../../develop/mcp.md)
- [Error codes](../errors.md)