Move the day of a task you filed

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

No annotations exist, so the description carries the full burden and does it well: it discloses the authorization boundary (agent-filed only, person-set days refused), the null semantics ('Send null to take a day off'), the blast radius ('Nothing else about the task changes'), and a durable constraint ('closing it is still never yours'). That is exactly the side-effect and permission context an agent needs before a mutation.

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 sentences, front-loaded with purpose, then scope refusal, then null handling and non-effects. Every clause carries information; the illustrative examples ('the meeting slipped a week') are short and earn their place.

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 3-parameter mutation with no annotations and no output schema, the definition covers who is affected, what is refused, and what is left untouched. It does not say what comes back on success or what happens when the named task doesn't exist or is already closed.

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%, so the schema already documents task id and the date/deadline format including null. The description reinforces the null behavior but adds no new syntax or constraints, so baseline 3 is right.

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 set and resource: change the `date` or `deadline` of a task, and names the exact field names from the schema. It also delimits the object ('a task an agent proposed'), which separates it from sibling `move` and from `propose`/`plan` without the agent needing to open either 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 a concrete trigger ('when what you learnt since moves it: the meeting slipped a week, the document arrived early') and an explicit exclusion ('a day the person set is theirs... is refused'). It never names a sibling by name, so an agent that wants to move something else (e.g. `move`) must infer the boundary itself.

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