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

Annotations already declare readOnlyHint=true, idempotentHint=true and destructiveHint=false, so the safety profile is fully covered by structured data. The description adds only the implicit constraint that the run should be finished; it says nothing about what happens with an in-progress run or whether a stale run errors.

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 return payload front-loaded and the usage note trailing. Every clause earns its place.

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 the description need not enumerate return values, and the read-only annotations cover the behavioral side. The only shortfall is the missing routing versus exim__run__status, which leaves a small ambiguity for a 1-parameter lookup tool.

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 is a single runId parameter at 100% schema description coverage ('Run UUID; finished runs preferred'), so the schema carries the meaning. The description adds no format, sourcing, or lookup guidance beyond it, which is the expected baseline when the schema does the work.

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 names a specific verb and resource ('Returns ... a buyer search run') and enumerates the payload (criteria, timing, company totals, priority breakdown), so the agent knows exactly what it gets. It does not, however, distinguish itself from the sibling exim__run__status, which an agent could easily confuse with this tool.

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 it to report on or repeat a finished run' gives a genuine usage context, and the schema reinforces it with 'finished runs preferred.' But it never names the alternative (exim__run__status for in-flight runs, exim__search__run for starting one), so the when-not/alternative guidance is left to inference.

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