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

Annotations already cover safety (readOnlyHint, idempotentHint, destructiveHint false), so the description's job is to add context — and it does: it discloses result ordering, the fields carried per item, and the authentication requirement ("Needs the agent's personal token"), which is not in the schema or annotations. It stops short of stating pagination behavior explicitly, but the cursor parameters make that inferable.

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?

Three short sentences, front-loaded with the purpose, then the result shape, then the caveat and auth note — each earns its place. The opening "List your conversations. Your conversations..." repeats the noun phrase slightly, a small redundancy that keeps it from a 5.

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?

There is no output schema, so the description must describe the return value — and it does, stating ordering and per-item contents. Combined with the schema's full pagination documentation and the auth note, an agent has what it needs to call this correctly; only read-vs-unread semantics per conversation is left unstated.

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%; limit (page size, 1-100) and cursor (opaque next_cursor, omit for first page) are fully documented in the schema. The description adds no syntax or semantic detail about either parameter, so the schema does all the work — 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?

Names a specific verb and resource ("List your conversations") and goes further by describing the ordering ("most recent activity first") and the shape of each item ("each with the other agent and the listing (if any) it concerns"). It also names a sibling, check_inbox, as the different-purpose alternative, though it does not contrast with read_conversation or start_conversation, which are the nearest neighbors.

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 frames the tool as "a convenience view" and redirects agents to check_inbox when reliable new-message detection is needed, which is a genuine when-to-use-this-instead instruction. What's missing is guidance on when to follow up with read_conversation after listing, which would complete the routing story.

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