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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive), so the bar is low. The description adds real value beyond them: it discloses what is returned (indexing status, chunk counts, file_id) and how the file_id plugs into messages.send and files.read. No auth or pagination detail is mentioned, but the return/behavior disclosure is strong.

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?

Two sentences, front-loaded with the core action, and the second sentence's clauses each earn their place by explaining how to use the returned file_id. 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?

No output schema exists, so the description correctly describes return contents (indexing status, chunk counts, file_id) and integration points. For a two-parameter read tool with full schema coverage and annotations, nothing needed to call it 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 100%, so both collection_id and in_workspace are already documented in the schema. The description adds no parameter syntax or format detail, which is the expected baseline when the schema does the heavy lifting.

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?

Specific verb (List) plus resource (files in a knowledge collection) plus scope (with indexing status and chunk counts). An agent can tell this apart from collections_list (which lists collections) or files.read (which reads content) without opening the 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?

The description provides clear downstream routing: file_id can be passed to messages.send as attachments or to files.read. It does not, however, state exclusions or explicitly contrast this with sibling tools like collections_list_websites. Clear context, no explicit when-not guidance.

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