messages-broadcast

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

No annotations are provided, so the description must disclose all behavioral traits. It describes the core behavior (resolves to_capability, dispatches per match) and the return format, but does not mention side effects, authorization requirements, rate limits, or what happens when some agents fail. Adequate but not comprehensive.

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?

The description is two sentences, front-loading the key distinction ('Fan-out variant of messages-send') and providing necessary details without redundancy. Every sentence adds value.

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 8 parameters all described in the schema and a clear return format, the description is largely complete. It lacks details on partial failure handling or mutual exclusivity of recipient parameters, but the schema fills those gaps. For a fan-out tool, the failure mode is addressed briefly.

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%, so baseline is 3. The description adds significant meaning to the 'to_capability' parameter by explaining the resolution process ('resolves to every online agent... whose capabilities list contains this value'). This goes beyond the schema's description of 'Capability string to fan out on.'

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?

The description clearly identifies the tool as a 'Fan-out variant of messages-send', stating the specific verb 'fan-out' and resource 'messages'. It distinguishes itself from the sibling tool 'messages-send' by indicating it broadcasts to multiple agents matching a capability.

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?

The description explicitly frames the tool as a variant of 'messages-send', guiding when to use it for broadcasting. It mentions that an error occurs if no agents match, but does not provide explicit when-not-to-use guidance or list other alternatives beyond the sibling.

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