list-supported-languages

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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is covered. The description adds that it returns localeInfo objects with locale and displayName, which provides some behavioral context. However, it does not disclose additional traits like potential latency, rate limits, or whether results are cached. The openWorldHint annotation signals non-determinism, which is not elaborated.

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?

The description is very concise: 4 sentences plus a front-loaded tip. It immediately states the purpose, then adds context, and finally provides actionable guidance. No redundant phrases, and each sentence serves a clear function.

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?

Given no output schema, the description adequately explains the return format (localeInfo objects). It also connects the tool to a real workflow (validating locale before updating settings). However, with 8 optional parameters, it does not guide which ones are relevant for this tool (e.g., filter/search may be unnecessary for a small list). Despite this, it is largely complete for a read-only list tool with good annotations.

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%, with detailed descriptions for all 8 parameters (top, skip, count, filter, etc.). The tool description does not add any additional parameter-level meaning beyond what the schema already provides. At high coverage, baseline of 3 is appropriate.

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?

The description clearly states the tool's purpose: 'Get the list of locales and languages that are supported for the user.' It identifies the specific resource (locales/languages) and related context (mailbox server configuration, Outlook client language selection). This uniquely distinguishes it from sibling tools like list-supported-time-zones.

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?

The description provides explicit use cases: 'When setting up an Outlook client, the user selects the preferred language from this supported list.' It also advises to 'Use this to validate the locale value before calling update-mailbox-settings.' This gives clear context and a concrete scenario, though it doesn't explicitly mention when not to use the tool or alternative tools.

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