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

Annotations already declare this a non-readOnly, idempotent, destructive write. The description adds useful context beyond that: the statement field is the only channel wording that may later be approved, and unsaved channels are excluded downstream. It stops short of explaining the destructive/idempotent behavior (e.g. overwriting an existing channel entry).

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?

Three short sentences, front-loaded with purpose, then channel values, then the statement rule and inclusion rule. No filler, though the enum restatement is slightly redundant with the schema.

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 values need not be described. However, with 7 parameters at 0% schema coverage and no mention of the concurrency-control field expectedRevision, the definition is not complete enough for an agent to call this mutation confidently.

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% across 7 parameters, so the description carries the full burden but only touches two of them. It restates the channel enum (already in the schema) and clarifies the statement field's downstream authority, but leaves name, catalogId, planId, status, and especially expectedRevision completely unexplained.

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 first sentence gives a specific verb and resource: storing a support channel the user has approved for one customer plan. It clearly reads as the write counterpart to list_plan_channels, though no sibling is named explicitly, so it falls just short of the 5 bar for sibling differentiation.

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 supplies a precondition (the channel must be explicitly approved by the user) and a consequence for skipping it (a channel not saved here is not included), which implies when to call it. It does not name an alternative tool or state when NOT to use it, so guidance stays implied rather than explicit.

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