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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so the safety profile is covered. The description adds genuinely non-obvious behavior: bookings happen over WhatsApp and must be confirmed by a person, and there is no booking API — so the agent knows it cannot complete a reservation and must hand off. Return-shape detail (pagination, size) is absent but not critical here.

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?

One dense sentence front-loads the resource and its highlights, then the booking channel; every clause carries information. The trailing bilingual fragment '/ Espacios y reservación.' repeats the title and adds no value, which is the only waste.

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?

With no parameters, no output schema, and full annotation coverage, the description supplies exactly what is missing: what each space record includes and how booking actually works. An agent has everything needed to call it and to interpret the result correctly.

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 tool takes zero parameters, so the schema requires no explanation and the baseline is 4. The description correctly presents the tool as parameterless enumeration, leaving nothing ambiguous about invocation.

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 the concrete resource (Lumi's spaces: free meeting room, work areas, private glass room, ~500 m² terrace) and states what the response contains: highlights, page URLs, and booking instructions. That is far more specific than a restatement of the name. It stops short of explicitly differentiating itself from read_page, even though it implicitly does so by bundling URLs and booking details.

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 this is the tool for 'what spaces exist and how do I reserve one' questions, since booking via WhatsApp is mentioned. There is no explicit when-to-use statement, no exclusion of siblings like read_page or get_business_info, and no note on whether this supersedes fetching individual pages.

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