launcher_preview

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

Annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=false, so 'Changes nothing' largely restates structured data. The description does add real behavioral context — that the tool evaluates the config against a point in time (suggesting schedules/rules) rather than returning the stored config. It stops short of saying what the output looks like or whether `config` is a path, a stored config, or an inline object.

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 with zero waste: the purpose is front-loaded, the format example is embedded where it is most useful, and the safety qualifier closes it. Every clause earns its 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 read-only preview with annotations covering safety and no output schema, the core need is knowing what is being previewed and at what time, both of which are covered. The remaining gap is the undefined shape of the required nested `config` parameter, which matters given nested input and low schema coverage.

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 only 33%, and only `device` is documented in the schema, so the description carries the burden for `at` and `config`. It partially compensates: the 'at=fri 22:30' example documents the accepted time format, and 'what a config would look like' implies `config` is the config object being previewed. However, the required nested `config` object's shape and source remain unexplained, leaving a significant gap at this coverage level.

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 states a specific operation on a specific resource: computing what a config would look like at a given time. This distinguishes it in spirit from launcher_get_config (fetch the real config) and launcher_set_config (mutate it), though no sibling is named explicitly. An agent can infer it is a simulation/preview, not a retrieval.

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?

Usage is implied rather than stated: the example 'at=fri 22:30' signals time-based rule evaluation, and 'Changes nothing' signals it is safe to call before applying. There is no explicit when-to-use or when-not-to-use versus launcher_get_config or launcher_set_config, so the agent must infer the preview-before-apply workflow.

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