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

Annotations already declare readOnlyHint/idempotentHint/destructiveHint=false, and the description adds context beyond them: 'Free, and it fetches nothing' (cost and no network/side effects) and 'keys are exact and guessed names are refused' (validation behavior that silently fails otherwise). It does not describe the return shape in depth, but the behavioral profile is well covered.

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 purpose, then the when-to-use rule, then sibling disambiguation, then the cost note. Dense but every sentence earns its place; slightly long for a zero-parameter tool.

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 no output schema and no parameters, the description carries the full burden and does so: it says what the response contains (each key with meaning and default, valid schedules, path glob behavior). An agent knows both what the tool is for and what it will get back.

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 tool takes zero parameters, so the baseline is 4. The description does not need to explain argument semantics, and the empty schema is consistent with a pure reference-lookup 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?

Specific verb and resource: lists the project settings an assistant can set, plus valid schedules and path glob semantics. It explicitly separates itself from the sibling get_project ('describes settings in general; get_project shows the values one project has'), so an agent can route without opening 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?

States exactly when to read it: before create_project, update_project, or a `config` argument, and specifically whenever the request names a section, schedule, format, limit or behaviour. It also gives the reason (keys are exact and guessed names are refused), which is actionable gating guidance with a named alternative.

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