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

Annotations already declare readOnlyHint=true and openWorldHint=false, so safety is covered; the description adds genuinely new context: the tool depends on reply-date data, results degrade without it, and the silence table is a conditional 'of those silent at day N, how many later heard back' construct rather than raw counts. It stops short of saying what happens when there are zero replies or too few data points, which is the one gap.

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?

Front-loaded with the core metric before the silence-table explanation, and every clause carries information — no filler. The middle sentence is long and stacks two outputs plus a threshold list, which slightly hurts scannability.

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?

An output schema exists, so return values need no explanation, and the description still pre-explains the non-obvious silence-table semantics and the data dependency. For a read-only, zero-required-param analytics tool, nothing an agent needs in order to call it correctly is missing.

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 both params (`by`, `since`) carry their own descriptions, including a cross-reference to funnel for `by`. The prose adds no format, enum, or value examples beyond the schema, 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?

States a specific verb+resource with real precision: median and 75th-percentile days from submission to first reply, plus a silence table with explicit day thresholds. This is clearly distinguishable from siblings like funnel, summary, and stale_applications, which an agent could otherwise confuse with it.

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?

Explicitly says 'Use it to decide when to close silent applications,' which ties the tool to a concrete decision and implicitly routes the agent away from stale_applications/summary. It also names the prerequisite (reply dates, filled by set_status or backfilled by check_tracker). It does not explicitly exclude or compare against the closest alternative, close_stale, so it falls short of a 5.

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