Qué cubre este MCP, y qué no

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

With no annotations, the description carries the full burden and does so well: it discloses no network access, that indices are packaged, that the full table is long, and that the parameter returns only one source's scope. This gives the agent a clear mental model of the tool's 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?

The description is compact and front-loaded: first sentence gives the core purpose, second adds usage timing, third clarifies parameter behavior. Every clause earns its place; no redundancy.

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 single-parameter tool with no output schema and no annotations, this description is complete. It covers purpose, when to use, network behavior, parameter effects, and output size expectations, making it self-sufficient for an agent.

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?

Although the schema already documents the 'fuente' parameter at 100% coverage, the description adds meaning: with the parameter it returns ONLY that source's scope (which 'usually is what's needed'), without it the full table is long. This advises on parameter choice and output size beyond the schema.

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 states the tool declares the real scope: which source answers each question, what is not covered, and the generation date of packaged indices. This specific verb-resource pair (declara alcance) clearly distinguishes it from sibling search tools by being a metadata/inventory tool.

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?

Explicit usage instructions: use it BEFORE concluding something doesn't exist from an empty search and to check if the index freshness is current. It also states 'No consulta la red' as an exclusion, clarifying it is not for live lookups among the sibling search tools.

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