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

Annotations already declare readOnly/idempotent/non-destructive, so the bar is lower, yet the description still adds real behavior: same OCR tolerance as the reader, original text preserved, adjacent pages drawn from the real fascicolo rather than invented numbers, and a 48000-character aggregate request cap. It also lists return fields (fonte_id, riquadri, termini presenti/mancanti, totale_brani, prossimo_brano), which is partly redundant with the output schema, keeping this from a 5.

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 core purpose, then limits, then return contract, then alternatives – a sensible order with no filler. A couple of defensive asides ('Non confonde punti trovati con articoli delimitati o fatti') are vague and cost a little tightness.

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?

Covers purpose, batch limits, per-passage limits, aggregate cap, return fields, continuation via prossimo_brano, and two alternatives. With an output schema present the return-field listing is optional, and the OCR-tolerance claim is left unquantified, but nothing needed to call the tool correctly 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 description coverage is 0% and parameter names are opaque Italian, so the description does the heavy lifting by glossing quanti as 'brani per pagina', caratteri as per-passage length, and inizio_brano as an offset, plus the undocumented 48000-character total limit. Defaults and ranges largely restate the schema, so it is good rather than exhaustive.

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 ('Legge i brani intorno ai riscontri') and adds scope ('anche quando sono in fondo a una pagina lunga'). It explicitly names the two siblings it is not, read_pages and verify_quote, so an agent can route without opening either schema.

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?

Gives explicit routing rules with conditions: use read_pages for full reading or when coordinates are missing, use verify_quote for citations on the passage's fonte_id. Combined with the batch-size limits (1-8 voci), the when-to-use picture is complete.

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