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

Annotations already declare readOnly, openWorld and non-destructive, so the safety profile is covered. The description adds genuinely useful behavior beyond that: the privacy guarantee 'Cotlet does not read your mailbox' and the auth requirement of a Cotlet API key with app access. It stops short of describing rate limits or the exact response shape, but the added context is substantive.

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 core answer is front-loaded, which is good, but sentences two and three largely restate sentence one ('Returns the address Wanderlog shows for forwarding confirmation emails to this trip'), and the closing auth sentence introduces the distinct term 'Cotlet' without explanation. Several sentences do not fully earn their place.

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 simple read-only getter with one fully documented parameter and full annotation coverage, the description covers what is returned (an address), how it is used, the privacy boundary, and the auth need. No output schema exists, but the return value is described in prose, so an agent has enough to call it correctly; only the response format's exactness is left implicit.

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 single trip_id parameter has 100% schema description coverage ('Trip ID from list_trips'), and the description only reinforces scoping with 'for this trip'. Per the high-coverage baseline, the schema already carries the parameter meaning, so 3 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 names a specific resource (the email address to forward flight/hotel/car confirmations to) scoped to a single trip, and its title ('Get booking import address') reinforces it. No sibling tool in the Wanderlog set returns this artifact, so an agent can distinguish it immediately without opening the schema.

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?

Usage is only implied: an agent can infer you call this to obtain the forwarding address, and the text explains what to do with the result ('Forward a confirmation from your mail client and Wanderlog fills in dates and times'). But there is no explicit when-to-use statement, no prerequisites sequencing, and no reference to alternatives such as wanderlog_get_trip.

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