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

The description adds behavioral context beyond the annotations: it explains what happens when the rule is hit (sends to notify channel, kept in inbox) and requires a key, pointing to external docs. It also provides the grammar rules and examples, which are critical for correct invocation. Since annotations do not cover these details, this is valuable. No contradiction with annotations.

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 moderately sized but efficiently structured: it opens with the core purpose and benefit, then details the grammar and examples, and ends with the key requirement. Every sentence adds value, and the grammar/examples are necessary for correct use. It is slightly longer than ideal but not verbose.

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 the single parameter, the description provides the complete grammar, examples, and the requirement for a key. It also explains the post-condition (hit sent to notify channel and inbox). It does not describe the return value, but there is no output schema, so that is not expected. The description is sufficient for an agent to construct a valid rule and know the side effects.

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 describes the 'rule' parameter with a description pointing to the grammar, and the schema description coverage is 100%. However, the parameter description is minimal ('The rule, in the grammar above.'), and the actual grammar details are only in the tool description. The description adds the full grammar and examples, which is essential. Since the schema does not fully define the expected format, the description compensates, but it is not significantly beyond what a good schema could provide. Baseline 3 is appropriate.

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 the purpose: setting a standing rule that the nest watches for while the user is away. It specifies the resource (rule) and the action (sets), and provides the grammar and examples, which distinguishes it from sibling tools like 'list_rules' and 'delete_rule'. It is very specific and actionable.

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 explains the operational context: use it to stop polling and receive alerts on the notify channel, with reference to set_webhook. It does not explicitly contrast with siblings like 'list_rules' or 'delete_rule', but the context makes it clear this is for creating rules, and the mention of the notify channel is a clear usage signal. No exclusions are given, but the purpose is unambiguous.

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