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

Annotations already declare idempotent, non-destructive, open-world behavior; the description usefully reinforces this by disclosing the no-op return ('synced: false when it was already up to date') and the refusal mode for unsupported source types. It omits permission/auth requirements and whether sync is synchronous or long-running, which would be the remaining valuable context.

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 tight sentences: the action and its eligibility constraint come first, the return-value edge case second. The trailing 'POST /sources/sync' is minor plumbing but costs almost nothing and aids debugging.

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 does describe the meaningful return value (synced: false on a no-op) and the error case, and annotations carry the safety profile. It leaves the mechanics of a sync and any auth or long-running-job behavior unstated, but nothing essential for a correct call 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?

There is only one parameter and schema coverage is 100%, with the schema already stating where the source id comes from (notebook_get_notebook or notebook_add_sources). The description adds no format, prefix, or validation detail about the id, so baseline 3 applies.

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 ('Re-import') and resource ('a Google Drive source') with the constraint that only Docs/Drive files qualify. It is clearly separable from siblings like notebook_upload_source or notebook_add_sources, which create sources rather than refresh an existing one.

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?

Explicitly gives the triggering condition ('after its file changed in Drive'), the exclusion ('other kinds of source are refused'), and a precondition check ('notebook_get_source shows inSync beforehand'). An agent knows both when to call it and which sibling to consult first.

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