msg_send

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

With no annotations, the description carries the full burden and does disclose meaningful behavior: task becomes a tracked job, routing to a live agent, reroute=false to disable, splitting a big task across the team, result returned, and reply showing Commons' knowledge. It omits auth/thread/threading semantics but covers the key side effects well.

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?

Front-loaded with the core action and target semantics, then layered detail on type and routing. Dense but every clause adds information; 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 10-parameter tool with no annotations and no output schema, the description leaves the majority of parameters unexplained and says little about the body format or threading. The behavioral notes are good but insufficient to call the tool correctly.

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 0% for 10 parameters, so the description must compensate but only explains three (to, type, reroute). Critical params (agent, thread, api_key, project, subject, reply_to) are undocumented in both the schema and the description.

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 opens with a specific verb and resource: 'Message one agent (to=name) or all (to="*")', immediately clarifying the target scope. It clearly distinguishes its behavior from the receiving counterpart msg_recv, though it doesn't name siblings explicitly.

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?

It enumerates the type values (message|task|question|review|fyi) and explains what task does, which implies when each mode applies, but there is no explicit 'use this instead of X' routing or when-not guidance. Usage is inferable rather than stated.

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