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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and closed-world scope, so the safety profile is covered. The description adds genuinely new behavioral context by warning that a negative result is inconclusive — absence does not prove deletion — which is exactly the kind of result-interpretation nuance annotations cannot express.

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 with the primary behavior front-loaded and no filler. The wording is slightly compressed to the point of being cryptic ('exact channel presence'), but nothing is wasted.

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?

An output schema exists, so return-value explanation is not required. Still, the description leaves open what 'presence' concretely means (boolean vs. state enum) and why absence might occur without deletion, which matters for a status-check tool whose whole value is interpretive confidence.

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%: both agent_id and channel_id carry UUID format plus provenance hints (agents_list/agent_create, channels_list). The description adds nothing about parameter semantics, so the schema does all the work and a baseline 3 is appropriate.

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 resource — reading the channel's presence under a given Agent — which is a concrete, checkable outcome rather than a restatement of the name. It does not, however, differentiate itself from nearby siblings such as channel_read, channel_removal_impact, or agent_removal_status, so the agent must infer the boundary from the tool name.

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 only implied: the tool is for checking whether a channel is still present under an Agent. The clause 'absence is not deletion receipt' acts as a partial when-not (don't treat this as confirmation of deletion), but no alternative tool is named for the deletion-confirmation case, even though channel_removal_impact exists.

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