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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive), and the description adds substantial context beyond them: a 20,000-character page limit, a download link that expires after 5 minutes, OAuth and trial/paid plan requirements, and the behavior that filled documents download as their editable Word/Excel original with a separate PDF variant. These are exactly the operational traits an agent needs before invoking the tool.

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 core capability and pagination guidance are front-loaded, and nearly every clause adds needed detail. The single dense block with stacked parentheticals is slightly hard to scan, but nothing is redundant.

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 output schema, the description still specifies the return values (text, download link, download_filename, pdf_download_url, pdf_filename) and their quirks. Auth, plan gating, pagination, and expiry are all covered, so an agent can invoke it correctly end to end.

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%, so the description must carry the full load, and it does: file_id is identified as coming from list_tender_files, and offset is explained through the next_offset pagination pattern. That compensates fully for the undocumented input 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 gives a precise verb and resource: fetch one file from the signed-in company's document archive, returning its text, pagination offset, and a download link. It immediately ties file_id to list_tender_files, so an agent can distinguish it from the sibling listing tool 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?

It states the prerequisite clearly ('file_id from list_tender_files') and explains how to continue paging ('pass next_offset as offset for the rest'), which is actionable usage guidance. It lacks an explicit when-not-to-use statement or named alternative for cases where the agent only needs metadata rather than file content.

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