Start FatSecret Auth

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

Beyond the annotations (readOnly=false, idempotent=false), the description discloses the multi-step nature: returns an authorize URL, requires the user to log in and approve, and yields a PIN. This gives valuable behavioral context that the annotations alone don't convey.

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 sentences, front-loaded with the core action, and every sentence adds essential flow information. No wasted words.

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 0-parameter auth-start tool with no output schema, the description fully covers the workflow, including the user's actions and the exact next step (fatsecret_complete_auth). It is sufficiently complete for an agent to select and invoke the 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?

The tool has zero parameters, so the schema is trivially complete. The description adds no parameter details, but none are needed; baseline of 4 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 uses a specific verb ('Start linking') and identifies the resource ('YOUR real fatsecret.com account'). It clearly differentiates from siblings like fatsecret_complete_auth and fatsecret_check_auth_status by outlining the initial step of the OAuth flow.

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?

It explains the intended use: to initiate linking a real FatSecret account and explicitly directs the user to pass the resulting PIN to fatsecret_complete_auth. This provides clear context and a named next step, though it doesn't explicitly state exclusions (e.g., when already authenticated).

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