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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=false, so the safety profile is covered. The description adds genuinely new context: account onboarding and plan limits gate the result, and the returned disclaimer must be preserved. That is real behavioral information beyond the structured fields.

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?

Four short sentences, front-loaded with the core action and followed by the trigger, the constraints, and the output caveat. Each sentence adds something, though 'in one of your Afterglow checklists' mildly duplicates the title.

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 an output schema present, return values need not be described, and annotations cover the read-only safety profile. The description supplies the usage trigger, plan-limit caveat and disclaimer handling. Only the module_id selection rationale remains thin.

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 0% for the single required module_id, so the description carries the burden. It does name the four category values (legal, money, home, coparenting), effectively restating the enum rather than explaining what the parameter does or how to choose a module. Minimal compensation for the coverage gap.

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 verb and resource: 'Show available items and saved progress in one of your Afterglow checklists.' That is enough to distinguish it from the write-side sibling set_checklist_status, though neither sibling is named explicitly. Purpose is clear but lacks explicit sibling differentiation.

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?

'Use when you ask for unfinished legal, money, home or coparenting checklist tasks' gives an explicit usage trigger tied to the four module categories. It does not state when NOT to use it or point to set_checklist_status for state changes, so it falls short of a full when/when-not/alternatives treatment.

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