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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so the safety profile is covered. The description adds real behavioral value by disclosing the specific diagnostic fields returned, including pause state and reason and next-run timing, which the annotations do not convey.

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 sentences, no filler, with the payload definition front-loaded and the usage cue immediately after. Every clause contributes either returned fields or a use trigger.

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?

There is no output schema, so the description must describe the return contents, and it does so comprehensively across sending state, pause, warmup, cap, bounce rate, and schedule. With annotations covering safety and a single well-documented parameter, an agent has everything needed to call it correctly.

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 description coverage is 100%, and the schema description for workspaceId already explains it is the site to act on and points to get_status for listing sites. The prose adds no additional parameter meaning, so the baseline of 3 applies.

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 enumerates exactly what the tool reports for a site: sending on/off, pause reason, warmup progress, daily cap and usage, bounce rate, and next run time. That is a specific resource with concrete contents, and it is clearly a diagnostic read rather than a mutation like set_sending or resume_sending. It stops short of a crisp verb-plus-resource opening (the verb is only implied by 'Read this'), so it is strong but not maximally sharp.

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?

It gives explicit triggering questions: 'why are so few emails going out' and 'why did it stop', which tells the agent exactly when this tool is the right call. It does not name a contrasting sibling or state when not to use it (e.g., versus get_status or set_run_settings), so it is clear context without explicit alternatives.

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