source_stats

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

With annotations present (readOnlyHint=false, openWorldHint=true, idempotent=true), the description adds real context: the no-notebook_id summary runs 'sin red ni cuota', while auto_sync can populate the cache and uncached sources are listed under not_cached. That reconciles the openWorld/write hints with the read-style summary. It stops short of describing cost or side effects of the auto-sync download path.

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?

Front-loads the resource and its metrics, then immediately covers the notebook_id-less case before the per-source case. Dense but every clause carries a mode distinction; slightly heavy in one paragraph but 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?

All four modes are accounted for and an output schema exists, so return values need not be spelled out. Given a read-mostly, four-optional-parameter tool with cache semantics, this is enough for an agent to invoke it 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?

Schema coverage is 100%, so the baseline is 3; the description nonetheless adds semantics beyond the schema — the meaning of an omitted notebook_id (whole-cache summary) and the behavioral consequence of auto_sync=False (cached-only plus not_cached list). Source_ids and terms are left to the schema, which is acceptable at full coverage.

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 ('Radiografía local de las fuentes') and enumerates exactly what is measured: tamaño, palabras, encabezados y términos dominantes. It also distinguishes the two operating modes (cache-wide vs per-source) and names the downstream siblings it feeds (sync_notebook, clear_cache), so an agent can tell it apart from search_sources or list_sources.

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 routing is given for every mode: omit notebook_id to get the cache-wide summary used to decide sync_notebook or clear_cache; pass notebook_id to measure source by source; set auto_sync=False to measure only cached sources. The when-to-use condition is stated rather than implied.

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