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

Annotations already declare readOnly, idempotent and non-destructive, so the safety profile is covered; the description adds real behavioral context beyond them: newest-first ordering, the concrete fields returned, the allowance-usage count, and the 'More:' cursor pagination convention. It stops short of stating limits (e.g. max 50 per page, default 20) or what an empty/allowance-exhausted result looks like.

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, zero waste: the purpose and return shape come first, then the search and next-step guidance. Every clause carries information an agent needs to decide or act.

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 compensates by enumerating the returned fields and the ordering, and it covers pagination and the natural follow-up tool. Nothing essential for correctly invoking or chaining this 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?

Schema description coverage is 100%, with limit, query and cursor all documented in the schema including defaults and bounds. The description's notes on `query` ('search titles and contents') and the cursor ('More:' line) largely restate the schema, so the 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 and resource ('List the user's bubbles') and immediately enumerates the exact return shape (id, title, source, size, date, preview, allowance usage) and ordering ('newest first'). This is far more than a restatement of the title and lets an agent distinguish it from get_bubble or list_deleted_bubbles 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?

Explicitly routes the agent: 'Start here, then read only the bubbles you need with get_bubble' names the alternative and the condition that selects it, and 'Pass `query` to search titles and contents' tells when to use the search mode. The only gap is that it never mentions the deleted/share siblings (list_deleted_bubbles, list_shares), which an agent could confuse with this listing tool.

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