Complete FatSecret Auth

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

Annotations declare readOnlyHint=false and idempotentHint=false, so the description is not expected to restate those. It adds the procedural detail about the PIN from fatsecret_start_auth, which is useful. However, it does not disclose side effects (e.g., token creation), error cases, or what happens if no auth flow is active. This is acceptable given the annotation hints but leaves some behavioral gaps.

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 a single, well-structured sentence that front-loads the key action ('Finish linking') and includes the necessary context (PIN source). No extraneous words or repetition.

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?

The tool is simple (one param) but lacks an output schema. The description covers the core usage but does not explain expected return values, error conditions, or the broader OAuth flow (e.g., that this is required for subsequent authenticated calls). Given the sibling tools provide flow context, it is minimally complete but not fully self-sufficient.

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%, as the only parameter 'verifier' is fully described in the schema. The description repeats the same semantic ('PIN FatSecret showed you') without adding new meaning beyond the schema. Baseline score of 3 is appropriate because the schema carries the heavy lifting.

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 function: finishing the FatSecret account linking process using a PIN. It names the specific verb 'Finish linking' and resource 'FatSecret account', and distinguishes itself from siblings like fatsecret_start_auth and fatsecret_check_auth_status by referring to the PIN shown after the start step.

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 clear context for when to use the tool: after fatsecret_start_auth, when the user has received a PIN. It implicitly differentiates from alternatives by anchoring to a prerequisite step, but it does not explicitly state when not to use it or list alternative tools.

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