MongoDB MCP Server

Official

by mongodb-js

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TypeScript

Remote

collection-indexes

Read-only

Retrieve all indexes for a MongoDB collection by providing connection ID, database, and collection name.

Instructions

Describe the indexes for a collection

Input Schema

TableJSON Schema

Name	Required	Description
`database`	Yes	Database name
`collection`	Yes	Collection name
`connectionId`	Yes	The connection to run the operation against. Use the id returned by one of the connect tools, or "preconfigured" to use the connection string the server was configured with.

Output Schema

TableJSON Schema

Name	Required	Description	Default
`searchIndexes`	Yes
`classicIndexes`	Yes
`searchIndexesCount`	Yes
`classicIndexesCount`	Yes

Schema Changelog

Changes observed during successful MCP inspections.

Changed3 schema fields changedv2.0.0Aug 4, 2026

addedInput schema / additionalProperties
```
Added value: +false
```

addedInput schema / properties / connectionId

Added value: +{
+  "description": "The connection to run the operation against. Use the id returned by one of the connect tools, or \"preconfigured\" to use the connection string the server was configured with.",
+  "type": "string"
+}

changedInput schema / required

Previous value: -[
-  "database",
-  "collection"
-]New value: +[
+  "connectionId",
+  "database",
+  "collection"
+]

Changed2 schema fields changedv1.11.0May 22, 2026

removedInput schema / additionalProperties
```
Removed value: -false
```

changedOutput schema / (root)

Previous value: -nullNew value: +{
+  "$schema": "http://json-schema.org/draft-07/schema#",
+  "additionalProperties": false,
+  "properties": {
+    "classicIndexes": {
+      "items": {
+        "additionalProperties": false,
+        "properties": {
+          "key": {
+            "additionalProperties": {},
+            "propertyNames": {
+              "type": "string"
+            },
+            "type": "object"
+          },
+          "name": {
+            "type": "string"
+          }
+        },
+        "required": [
+          "name",
+          "key"
+        ],
+        "type": "object"
+      },
+      "type": "array"
+    },
+    "classicIndexesCount": {
+      "type": "number"
+    },
+    "searchIndexes": {
+      "items": {
+        "additionalProperties": false,
+        "properties": {
+          "latestDefinition": {
+            "additionalProperties": {},
+            "propertyNames": {
+              "type": "string"
+            },
+            "type": "object"
+          },
+          "name": {
+            "type": "string"
+          },
+          "queryable": {
+            "type": "boolean"
+          },
+          "status": {
+            "type": "string"
+          },
+          "type": {
+            "type": "string"
+          }
+        },
+        "required": [
+          "name",
+          "type",
+          "status",
+          "queryable",
+          "latestDefinition"
+        ],
+        "type": "object"
+      },
+      "type": "array"
+    },
+    "searchIndexesCount": {
+      "type": "number"
+    }
+  },
+  "required": [
+    "classicIndexes",
+    "searchIndexes",
+    "classicIndexesCount",
+    "searchIndexesCount"
+  ],
+  "type": "object"
+}

First observedAug 18, 2025

TDQS

A3.7/5.0

Behavior3/5

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

The description does not add behavioral context beyond what the annotations already declare (readOnlyHint=true, destructiveHint=false). It is consistent with being a read-only operation, but lacks details about output structure or edge cases. With strong annotations, the bar is lower, but no extra context is given.

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 a single succinct sentence with no redundant information, front-loaded with the verb 'Describe'.

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 metadata inspection tool with a complete schema and output schema present, the description sufficiently conveys the tool's purpose. No critical information is missing for an agent to select and invoke it.

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

Parameters3/5

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

The input schema already provides full descriptions for all three parameters (database, collection, connectionId), and the tool description does not add any parameter-specific meaning. With 100% schema coverage, the baseline of 3 applies.

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 'Describe the indexes for a collection' uses a specific verb ('Describe') and identifies the resource (indexes for a collection). It is distinct from sibling tools like collection-schema and collection-storage-size, which cover different aspects of a collection.

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

Usage Guidelines2/5

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

No guidance is provided on when to use this tool versus alternatives. The description only states the tool's function without specifying prerequisites, exclusions, or alternative tools, resulting in no usage direction.

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