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

Annotations only cover readOnlyHint, so the description carries the rest and does add real value: it discloses that both inbound and outbound messages are returned, that results are newest-first, that pagination is cursor-based, and even names the underlying endpoint. It stops short of describing the per-message payload, which the missing output schema leaves undocumented.

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?

A single tight sentence plus the API reference line; scope, direction, ordering, and paging form are all front-loaded with 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?

For a two-parameter, filterless list tool with no output schema, the description covers what is returned (both directions, newest first, cursor-paged). What each message record contains is left unstated, but that is a modest gap given the tool's simplicity.

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 limit and starting_after are already documented in the schema. The description adds no parameter-level detail (e.g., default page size or cursor semantics), 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 (list) and resource (WhatsApp messages) with scope (workspace), direction (inbound + outbound), ordering (newest first), and pagination style (cursor page). The channel-specific resource name cleanly separates it from bird_list_sms_messages and bird_list_email_messages.

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?

No indication of when to use this listing tool versus bird_get_whatsapp_message or bird_list_whatsapp_templates. The scope phrase 'for the workspace' describes behavior, not selection criteria, so the agent must infer usage from the name alone.

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