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

Annotations declare openWorldHint/idempotentHint=false, and the description goes further by disclosing that the current name remains in effect until Meta approves and that the result arrives asynchronously via the placement.name_status_updated webhook. That async, externally-gated behavior is exactly the kind of context annotations cannot convey; only the lack of failure/rejection handling keeps it from a 5.

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 tightly written sentences: the action first, then the consequence. Every clause earns its place with no redundancy.

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 explaining how the outcome is delivered (webhook event name), which is the key thing an agent needs to know for an asynchronous approval flow. Nothing essential 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% and all three parameters are documented in the schema, including the pointer to profiles_placements. The description adds no parameter-level detail, 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?

Specific verb+resource ('Submit a new display name') with clear scope — Meta review — that separates it from whatsapp_display_name_get (which reads the current name) and whatsapp_business_profile_update.

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?

Usage is implied by the purpose and the review workflow, but the description never states when to prefer this over siblings such as whatsapp_display_name_get for checking status, nor any prerequisite (e.g. needing profile_id/phone_number_id from profiles_placements). Adequate but no explicit routing guidance.

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