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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, closed-world), so the description's main contribution is the return payload. It also scopes the tool to 'licitación abierta', which is useful behavioral context. It says nothing about failure modes for unknown or expired ids, and the return-field list, while welcome, is enumerating content rather than disclosing behavior.

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?

A single front-loaded sentence: purpose first, then provenance of the id, then the returned fields. Every clause carries information, though the long field enumeration is dense and would read better as a short list.

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?

There is no output schema, so the description must carry the return-value burden — and it does, naming organ, budget with/without VAT, estimated value, duration, lots, award criteria, procedure, deadline, official notice link and the bidalto.com record. For a one-parameter read tool, nothing essential is missing.

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 parameter already documents the 10-character id format with an example. The description's mention of the id and its search_tenders provenance restates what the schema already says, adding no new syntax or constraint, so the baseline 3 applies.

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 ('Devuelve el detalle de una licitación') plus the lookup key (id), and ties the id to search_tenders, which lets an agent place it in the search-then-detail workflow. It stops short of an explicit contrast with siblings, but the resource and access pattern are unambiguous.

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?

The parenthetical '(el que da search_tenders)' makes the intended call sequence clear: run search_tenders first, then fetch detail with the returned id. There is no explicit when-not guidance (e.g. what to do for closed tenders or invalid ids), so it falls short of a 5.

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