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

Annotations already declare destructiveHint/idempotentHint, but the description adds substantial context beyond them: cascading deletion of comments, per-channel id semantics, repetition-collapsing behavior ('deleting it deletes every repetition'), the side effect that published posts stay live on the network, and irreversibility. It even points at output.errors for failure diagnostics.

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 trigger condition and prerequisite, then the behavioral caveats. Six sentences is on the long side but each carries distinct information (comments, per-channel ids, repetitions, publish semantics, irreversibility); nothing reads as 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?

Covers trigger, prerequisite lookup, id scope, cascade behavior, cross-system effects, irreversibility, and error reporting (output.errors). With an output schema present, no further return-value explanation is needed; nothing an agent needs to call this destructively correct is missing.

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, but the description adds real meaning: the id identifies a single channel's copy of a post, and a multi-channel post has a separate id per channel, plus how repeating posts share an id. That is semantics an agent cannot get from the schema's bare 'id of the post to delete'.

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+resource ('delete an existing post') and enumerates the states it applies to (scheduled, draft, published, errored), which immediately separates it from create/update siblings. An agent can tell exactly what this tool does without opening the 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 usage context ('when the user wants to delete an existing post') and a prerequisite workflow: find the post first via list-your-posts and pass its id. It references 'list your posts' rather than naming the concrete sibling postsListTool, so the routing is slightly indirect but still actionable.

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