list_domains

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

Given no annotations, the description adds behavioral context: domain drift over time, exact matching by siblings, and ordering by most recent activity. It does not discuss side effects or permissions, but as a read-only list tool, this is adequate. The output schema exists to cover return values.

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 concise with 5 sentences, each adding value. It is front-loaded with the core purpose and provides necessary context. Could be slightly more streamlined, but overall efficient.

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 zero-parameter tool with an output schema, the description covers purpose, use case, and ordering. It lacks detail on authentication or potential empty results, but these are minor. Overall, it is complete enough for effective use.

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?

There are no parameters, and schema coverage is 100%. The description adds meaning by explaining what the list contains (distinct domains with memory count and latest activity), which is valuable beyond the empty schema.

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 'List distinct domains with their memory count and latest activity', specifying the verb and resource. It distinguishes itself from siblings by explaining its role in warm-up discovery to get exact domain strings that pulse and list_by_domain match exactly.

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 explicitly advises using this tool for warm-up discovery before using pulse or list_by_domain, which require exact matching. It tells when to use the tool and implies alternatives, providing clear guidance.

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