Check authentication status

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

The description adds valuable behavioral context beyond annotations: it states the tool is read-only ('Reads only; it never creates or rotates a key'), clarifies that 'not authenticated' is a successful response rather than an error, and describes the three distinct states it distinguishes. This is rich detail beyond the readOnlyHint and idempotentHint annotations.

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 three sentences, each earning its place: purpose, usage trigger with alternative, and behavioral disclosure. It is front-loaded with the core purpose and contains zero fluff. Every clause contributes actionable information.

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?

For a tool with no parameters and no output schema, the description is remarkably complete. It covers purpose, when to use, failure semantics (no-key state and login fallback), what it does not do (create/rotate keys), and how it differs from sibling tools (upgrade, get_profile). This fully equips an agent to invoke it correctly.

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?

The tool has zero parameters, which sets a baseline of 4. The description appropriately focuses on what the tool inspects (the stored key state) rather than parameters, and there is no schema detail to repeat. The description adds no parameter-specific meaning, but none is needed.

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: 'Report whether this client holds a working Misar.Blog API key, and which account it belongs to.' It uses a specific verb ('report') and resource ('Misar.Blog API key') and distinguishes it from siblings by explicitly referencing login, upgrade, and get_profile as alternatives for other actions.

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 when-to-use guidance: 'Run it first when anything is failing with an auth error, and before a run of write operations.' It also gives a conditional action: 'If it reports no key, run `login`.' This clearly differentiates it from write operations and other auth-related tools.

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