Retrieve Gmail labels or Outlook categories for a connected account. Use it to see available labels or categories before organizing messages.
List Gmail user labels or Outlook categories for an account.
| Name | Required | Description | Default |
|---|---|---|---|
| accountId | No | Account to operate on. Optional when exactly one account is connected. |
| Name | Required | Description | Default |
|---|---|---|---|
| data | Yes |
Changes observed during successful MCP inspections.
v0.11.1Output schema / $schemaRemoved value: -"http://json-schema.org/draft-07/schema#"v0.11.0Output schema / (root)Previous value: -nullNew value: +{
+ "$schema": "http://json-schema.org/draft-07/schema#",
+ "additionalProperties": false,
+ "properties": {
+ "data": {
+ "items": {
+ "additionalProperties": true,
+ "properties": {
+ "id": {
+ "type": "string"
+ },
+ "name": {
+ "type": "string"
+ }
+ },
+ "required": [
+ "id",
+ "name"
+ ],
+ "type": "object"
+ },
+ "type": "array"
+ }
+ },
+ "required": [
+ "data"
+ ],
+ "type": "object"
+}v0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
readOnlyHint=true already establishes the safe-read profile, so the description's main added value is noting the result varies by provider (Gmail labels vs Outlook categories). It says nothing about pagination or ordering, and the output schema covers the return shape.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
One short sentence, front-loaded with the verb and the provider-dependent resource. Nothing extraneous.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
An output schema exists, so return values need not be explained, and the provider-dependence of the result is noted. The remaining gap is the ambiguity against list_folders, which a one-clause clarification would resolve.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema description coverage is 100% for the single accountId parameter, so the schema already carries the semantics including the optional-when-one-account rule. The description adds no parameter detail beyond that baseline.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
States a specific verb (list) and resource (Gmail user labels / Outlook categories), scoped to an account. It does not differentiate itself from the nearby list_folders sibling, leaving an agent to guess whether labels and folders are the same concept.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
No indication of when to use this over list_folders or other list_* siblings, and no prerequisites or exclusions stated. Usage must be inferred entirely from the name.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.