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

Annotations already declare the write/idempotent/non-destructive profile, but the description adds genuine context beyond them: the account and explicit-consent requirement, and that the call returns data plus source/freshness metadata. It does not say what happens to unspecified fields or the failure modes on a missing consent, keeping it from a 5.

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?

Three short sentences with the core action front-loaded, then prerequisites, then units/returns. The units sentence feels grafted on and is not tied to any field, but nothing is padded.

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 mutation tool with no output schema, the description helpfully signals the return shape and the consent requirement, and annotations cover the safety profile. However, with a nested body of eight undocumented properties, an agent lacks the field-level detail needed to invoke it correctly, so it is only minimally complete.

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% across eight nested body properties (lat, lon, kind, name, sort, notes, boatId, spotId, activity), and the description explains none of them. The generic units line ("ft, kt, s, F, mi") does not map onto any of these fields, so the description fails to compensate for the coverage gap.

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?

States a specific verb+resource ("Update specified saved-place fields"), which cleanly separates it from siblings like update_my_trip and update_my_settings by resource. It stops short of naming any sibling or distinguishing itself from save_my_place/delete_my_place explicitly, and "specified fields" is left vague.

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 states a prerequisite (account + explicit consent) but gives no when-to-use vs when-not guidance and never mentions alternatives such as save_my_place (create) or get_my_place (read). An agent must infer the routing from the name alone.

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