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TypeScript
Remote

Get the full schema of a tool

get_tool_schema
Read-onlyIdempotent

Retrieve the full JSON schema of a specified tool from a named MCP server to construct valid arguments for calling it.

Instructions

Get the full description and JSON input schema of one tool, needed to construct arguments for call_tool.

Input Schema

TableJSON Schema
NameRequiredDescriptionDefault
toolYesTool name from list_tools
serverYesServer name from list_servers

Output Schema

TableJSON Schema
NameRequiredDescriptionDefault
nameYes
serverYes
annotationsNo
descriptionYesThe full description, untruncated.
inputSchemaYesJSON Schema for the arguments of call_tool.
outputSchemaNoJSON Schema the structuredContent of a call conforms to; absent if the tool declares none.

Schema Changelog

Changes observed during successful MCP inspections.

  1. Changed2 schema fields changedv0.11.2
    • changedInput schema / $schema
      Previous value: -"http://json-schema.org/draft-07/schema#"New value: +"https://json-schema.org/draft/2020-12/schema"
    • changedOutput schema / (root)
      Previous value: -nullNew value: +{
+  "$schema": "https://json-schema.org/draft/2020-12/schema",
+  "additionalProperties": false,
+  "properties": {
+    "annotations": {
+      "additionalProperties": true,
+      "properties": {},
+      "type": "object"
+    },
+    "description": {
+      "description": "The full description, untruncated.",
+      "type": "string"
+    },
+    "inputSchema": {
+      "additionalProperties": true,
+      "description": "JSON Schema for the arguments of call_tool.",
+      "properties": {},
+      "type": "object"
+    },
+    "name": {
+      "type": "string"
+    },
+    "outputSchema": {
+      "additionalProperties": true,
+      "description": "JSON Schema the structuredContent of a call conforms to; absent if the tool declares none.",
+      "properties": {},
+      "type": "object"
+    },
+    "server": {
+      "type": "string"
+    }
+  },
+  "required": [
+    "server",
+    "name",
+    "description",
+    "inputSchema"
+  ],
+  "type": "object"
+}
  2. First observedv0.9.0

TDQS

A4.4/5.0
Behavior3/5

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

Annotations already declare readOnly and idempotent traits; the description adds no extra behavioral context (e.g., errors or side effects). It does not contradict annotations, but also does not enhance beyond them.

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 concise—two sentences—and directly states the action, object, and purpose without redundant wording.

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

Completeness5/5

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

For a simple read-only schema retrieval tool, the description covers purpose, parameters, and use case sufficiently. No output schema is needed since the description explicitly says it returns the schema.

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

Parameters5/5

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

Both parameters (tool, server) are described with clear origins: 'Tool name from list_tools' and 'Server name from list_servers', providing complete semantic meaning and matching the 100% schema coverage.

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 'Get the full description and JSON input schema of one tool' and specifies its purpose for constructing arguments to call_tool, effectively distinguishing it from sibling tools like list_tools or call_tool.

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

Usage Guidelines4/5

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

Provides explicit usage context ('needed to construct arguments for call_tool'), indicating when to use it. Does not explicitly mention alternatives or when not to use, but the purpose is clear enough for most scenarios.

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

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