get_actionable_threads

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

Annotations already declare readOnlyHint=true, so the description is not required to reiterate safety. It adds context about ranking by urgency and filtering for action, but does not disclose deeper behavioral traits like indexing behavior or response format. With annotations covering the safety profile, a score of 3 is appropriate.

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 only three sentences, each with clear purpose: first sentence states the core function, second gives usage context, third references alternatives. No wasted words, front-loaded with the key action.

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 tool has 6 parameters and no output schema, the description provides adequate context: what the tool does, when to use it, a key parameter (pendingOn), and sibling distinctions. It does not explain the return format or pagination, but with high schema coverage and read-only annotation, it is sufficiently complete for correct usage.

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 100%, so the schema already documents all parameters. The description adds a small extra note about the pendingOn filter ('to distinguish threads waiting on you vs. them'), which reinforces the schema. However, it does not significantly extend understanding beyond the parameter descriptions, so baseline 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 clearly states 'Return mailbox threads ranked by reply urgency, filtered to those requiring action' with a specific verb and resource. It distinguishes from siblings by naming get_inbox_digest and get_threads, explaining their different scopes.

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 says 'Use for daily triage to surface what needs a response from you' and provides alternative tools with reasons: 'Prefer get_inbox_digest for a broader summary including stale items' and 'Prefer get_threads for an unranked thread list'.

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