perseus

perseus_list

Read-only

List directory contents or structured data to discover files. Supports sorting by name, modified time, or size. Read-only.

Instructions

List directory contents or structured data. Use to discover files before reading with perseus_read. Supports sorting by name, modified time, or size. Read-only; for hierarchical view, prefer perseus_tree.

Tool call template

Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {
      "path": "<path>"
    },
    "name": "perseus_list"
  }
}

Input Schema

Name	Required	Description
`path`	Yes	Directory path to list (default: workspace root)
`sort`	No	Value for sort parameter
`limit`	No	Value for limit parameter

Output Schema

Name	Required	Description	Default
`count`	No
`entries`	No

Schema Changelog

Changes observed during successful MCP inspections.

Changed5 schema fields changedv1.0.10Jun 27, 2026

changedInput schema / properties / limit / description

Previous value: -"Maximum number of entries to return"New value: +"Value for limit parameter"

addedInput schema / properties / path

Added value: +{
+  "description": "Directory path to list (default: workspace root)",
+  "type": "string"
+}

changedInput schema / properties / sort / description

Previous value: -"Sort order: name, modified, size"New value: +"Value for sort parameter"

changedInput schema / required

Previous value: -[]New value: +[
+  "path"
+]

changedOutput schema / (root)

Previous value: -nullNew value: +{
+  "properties": {
+    "count": {
+      "type": "integer"
+    },
+    "entries": {
+      "items": {
+        "properties": {
+          "modified": {
+            "description": "Last modified timestamp",
+            "type": "string"
+          },
+          "name": {
+            "type": "string"
+          },
+          "size": {
+            "description": "Size in bytes",
+            "type": "integer"
+          },
+          "type": {
+            "description": "file or directory",
+            "type": "string"
+          }
+        },
+        "type": "object"
+      },
+      "type": "array"
+    }
+  },
+  "type": "object"
+}

Changed2 schema fields changedv1.0.7Jun 10, 2026

changedInput schema / properties / limit / description

Previous value: -"limit= modifier for @list"New value: +"Maximum number of entries to return"

changedInput schema / properties / sort / description

Previous value: -"sort= modifier for @list"New value: +"Sort order: name, modified, size"

First observedv0.1.0May 27, 2026

TDQS

A4.6/5.0

Behavior4/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnlyHint=true, and the description reinforces 'Read-only'. It adds context by stating 'Supports sorting by name, modified time, or size', which goes beyond the schema's vague description for the sort parameter. No contradictions with annotations.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is two sentences with no wasted words. It front-loads the purpose and then adds usage guidance and features in a logical order.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness4/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the presence of an output schema and 100% schema coverage, the description covers purpose, usage, sorting behavior, and read-only nature. It could be more specific about what 'structured data' refers to, but overall it is sufficiently complete for a list tool.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters4/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, so baseline is 3. The description adds value by clarifying the sort parameter's possible values ('name, modified time, or size'), which the schema only describes as 'Value for sort parameter'. The path parameter is also implied in the first sentence.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states 'List directory contents or structured data' which is a specific verb and resource. It distinguishes from sibling tools by explicitly mentioning 'Use to discover files before reading with perseus_read' and 'for hierarchical view, prefer perseus_tree.'

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines5/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides explicit guidance on when to use this tool ('before reading with perseus_read') and when to use an alternative ('for hierarchical view, prefer perseus_tree'). It also states it is read-only.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.