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

Annotations already declare destructiveHint=true, so the safety profile is covered. The description adds the useful precondition about unstarted runs, but does not explain the destructive aspect (overwriting the prior delay), required permissions, or whether the old schedule is recoverable.

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?

Two short sentences, front-loaded with the action and then the constraint. The trailing API endpoint is mildly redundant but inexpensive. 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 simple two-required-parameter mutation with no output schema, the description covers the action, the precondition, and the underlying API call. Only the semantics of replacing an existing delay and permission requirements are left unstated.

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% and both parameters (delay, run_id) are documented with format examples in the schema. The description adds nothing beyond that, so the baseline 3 applies.

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: changing when a delayed run executes. It also confines the operation to runs that have not started, which sharpens the scope. It doesn't name a sibling (e.g., replay_run) to contrast against, so it falls just short of a 5.

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?

"Only applies to runs that have not started" is an explicit when-not condition an agent can check before calling. However, it names no alternative tool for runs that have already started (replay_run or cancel_run would be the natural siblings), so routing guidance is incomplete.

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