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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is covered. The description adds meaningful domain context: it explicitly states that only metadata/approved fields are returned and that secrets, contacts, and original files are excluded, which is valuable for an agent assessing data exposure.

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?

Two short sentences with the core purpose and data-scope constraint front-loaded. The phrase 'through the existing application' is slightly vague filler, but overall the description is efficient and free of redundancy.

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?

With no output schema, the description should clarify return values and pagination behavior, but it only states that metadata/approved fields are returned without specifying which fields or how limit/offset work. Annotations cover safety, making the definition minimally adequate but with clear gaps for a list tool.

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 0% for all three parameters (limit, query, offset), and the description provides no explanation of their meaning, defaults, or usage. It does not compensate for the schema's silence on pagination or filtering.

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 states a specific verb ('Read') and resource ('authorised api key metadata'), and adds a scope limitation ('Metadata/approved fields only; no secrets, contacts or original files'). It does not explicitly differentiate from analogous siblings like list_oauth_app_metadata or list_webhook_metadata, but the resource is clear.

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?

There is no guidance on when to use this tool versus alternatives, no prerequisites, and no exclusions. The implied usage ('read authorised api key metadata') is obvious from the name but not elaborated in the description.

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