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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is covered. The description adds genuine behavioral context: the response embeds capacities (guest-group min/max limits), and it shows the exact PostgREST query shape (select=*,capacities(*)), which tells the agent what data comes back without an output schema.

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 short sentences, front-loaded with the resource and scope, then the concrete query. No filler.

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 single-record read with annotations covering safety and 100% schema coverage, the definition is nearly sufficient, and it usefully discloses the embedded capacities relation in lieu of an output schema. Minor gap: no mention of not-found/error behavior.

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 coverage is 100% and the single product_id parameter is fully documented as a UUID with a regex pattern. The description adds only that the id is interpolated into the query, so the baseline of 3 applies — the schema does 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?

States a specific verb and resource ('One product by id') plus an important scope detail: capacities are embedded. An agent can distinguish this single-record fetch from bookingmood_list_products or bookingmood_search_products, though those siblings are not named.

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 implied — call it when you already have a product UUID — but there is no explicit when-to-use/when-not or pointer to list_products/search_products for discovery. Adequate but leaves routing to inference.

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