Update part of a day plan

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

Without annotations, the description must disclose behavioral traits. It indicates a mutating operation (edit, mark done, add, reshuffle) and partial update behavior. However, it does not mention idempotency, authorization needs, or what happens on failure. Basic transparency but not comprehensive.

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?

The description is two sentences long, front-loading the action verbs and then providing the critical partial-update instruction. Every sentence adds value with no fluff.

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?

Given 6 parameters, no schema descriptions, no output schema, and a complex nested structure (todos, schedule), this description is too minimal. It omits parameter semantics, return format, and error conditions, leaving significant gaps for the agent to infer.

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?

The schema has 0% description coverage for parameters. The description hints at `todos` and `schedule` via 'mark blocks/to-dos done, add items, reshuffle' but does not explain `date`, `mode`, `summary`, or `weekly_ref`. The agent gains little parameter meaning beyond the schema structure.

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 description clearly states that the tool edits an existing day plan, with specific actions like marking items done, adding, and reshuffling. The title reinforces 'Update part of a day plan', and the verbs distinguish it from creating or reading plans.

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 provides key usage guidance by instructing to 'Pass ONLY the keys you are changing; everything else is kept.' However, it does not mention when to use this tool versus alternatives like plan_day or save_plan, nor does it give context about prerequisites or restrictions.

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