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

Annotations already declare readOnly, idempotent, non-destructive and closed-world, so the description is not burdened with safety disclosure. It adds real value by explaining what the response contains (status and counts) and that counts track messages 'as WhatsApp reports it', implying they update over repeated reads.

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, front-loaded with the resource and payload, then the usage/routing hint. The only minor waste is echoing the title ('Get a broadcast') as the first line, which duplicates structured data.

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 reasonably carries the return-value burden by naming status and counts. Safety is covered by annotations and both parameters by the schema, leaving little an agent needs that is missing, though the exact shape of the counts is not elaborated.

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 coverage is 100% and both parameters (agent_id, broadcast_id) are fully documented with error codes in the schema itself. The description adds no syntax, format, or meaning beyond what the schema already provides, 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 singular resource ('Get a broadcast', 'One broadcast') and immediately scopes the payload to its status and counts. It also names the sibling listBroadcastRecipients, so an agent can distinguish it from list_broadcasts (plural) and list_broadcast_recipients without opening any 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?

Gives clear routing to an alternative: use listBroadcastRecipients when per-recipient detail is needed, and this tool for overall status/counts. It also implies the polling pattern ('read it again to follow a broadcast'), but there are no explicit exclusions or prerequisites beyond that.

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