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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so safety is covered. The description adds genuinely non-obvious behavior: contact details are deliberately withheld and are exchanged by iscabox only after the guide accepts a reservation, which shapes downstream agent behavior. It does not cover error cases for an invalid guide_id.

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 what the tool returns, followed by the privacy constraint. Dense but every clause carries payload information; the field enumeration is long yet justified for a no-output-schema tool.

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?

Single required integer parameter, no output schema, so the description carries the full burden of describing the return shape. It does so field by field and additionally states what is excluded, leaving nothing an agent needs in order to call it or interpret the result.

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%, so the schema already documents guide_id, including the search_destinations source that the description omits. The description's mention of find_guides adds nothing beyond the schema text. Baseline 3 applies where the schema does the work.

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 resource (public profile of a registered guide) plus the exact key that selects it (guideId from find_guides) and enumerates the payload: photos, offerings, boats with type/size/engine/seats, served locations with daily rate and fish, and equipment inclusion. An agent can distinguish this from find_guides (search) without opening any 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?

Implies the workflow clearly: the guide_id comes from find_guides, so this is a lookup of an already-identified guide rather than a discovery tool. It also sets a firm boundary on what cannot be obtained here (phone, email, Instagram), pointing the agent to the booking flow instead. No explicit named alternative is given for the search case, which keeps it at 4.

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