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

Annotations declare destructiveHint=true and idempotentHint=false; the description adds real context by narrowing the blast radius ('that status is the only thing it writes') and warning that it does not schedule the next step, preventing a false success claim. The remaining gap is silence on whether a skip can be undone or what happens when the activity is not pending, which matters given destructiveHint=true and idempotentHint=false.

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?

Four short sentences, front-loaded with the verb and status written, then the caveat, the id-type warning, and the alternative. No sentence is redundant and each carries a distinct constraint.

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 one parameter, full schema coverage, and annotations covering the safety profile, the description supplies nearly everything needed: effect, non-effect, follow-up verification, and an alternative tool. Only the failure mode (non-pending or unknown activityId) and reversibility are unaddressed.

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% and the single parameter already documents its source (`activity_list`), so the baseline is 3. The description adds disambiguation beyond the schema by stressing it acts on an activity id rather than a lead id, which is the most likely caller error for this tool.

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 ('Mark one pending action SKIPPED') plus the scope constraint ('one pending action', 'activity id, not a lead id'). It explicitly distinguishes itself from `lead_update` and points to `lead_flow_state` for follow-up, so an agent can separate it from adjacent flow/lead tools without opening any 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 the triggering condition ('unblock a lead stuck on a step that will never succeed'), the alternative for a different intent ('to stop a lead entirely use `lead_update` with `paused` or `isExcluded`'), and the post-call action ('re-read with `lead_flow_state`'). When-to-use, when-to-use-something-else, and what-to-do-next are all present.

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