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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=false, so the safety profile is covered. The description adds real context beyond that: result ordering (most recently changed first), the exact return shape (names and ids, no cell data), and the access-scoping rule that explains why results can be fewer than expected.

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?

Four short sentences, purpose front-loaded, each adding distinct information (scope, ordering, return shape, filtering, access caveat). No restatement of the title or name.

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 correctly carries the return-value burden (names and ids only, ordering). It is nearly complete, though the reference to 'page size' hints at pagination that has no corresponding parameter in the schema, leaving a small ambiguity about result limits.

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 only 50%: mailbox is documented in-schema (with a pointer to list_authorized_mailboxes) but query has no schema description. The description compensates by explaining what query does ('narrow by name'), so both parameters now carry usable meaning.

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 ('Find spreadsheets in the user's Drive') with scope (most recently changed first). The clause 'Returns names and ids only — no cell data' cleanly separates it from get_google_spreadsheet and read_google_sheet_range, so an agent can place it without opening another 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 one concrete usage tip ('Pass a query to narrow by name') and a caveat about folder scoping, which is implied guidance. However, it never names an alternative tool (e.g. list_gdrive_items or get_google_spreadsheet) or states when-not-to-use, so routing still requires inference.

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