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

Annotations already declare readOnlyHint=true, idempotentHint=true and destructiveHint=false, so safety is covered. The description adds genuinely new behavioral context: results are ordered newest first, and each run includes cost information, which is return-content detail not present in the annotations or schema. It still omits pagination/truncation behavior at the limit boundary, so it falls short of a 5.

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?

A single front-loaded clause with no filler; ordering and return content come before the optional filter enumeration. It is slightly elliptical ('with cost') and lacks an explicit verb, which keeps it from a 5.

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?

For a six-parameter read-only list tool with no output schema, the description covers the core semantics and hints at returned cost data. It does not explain the limit ceiling of 50, what defaults apply, or how workflow_id scope relates to share_id scope, leaving gaps an agent must resolve from the schema alone.

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 83%, so the schema already documents kind, limit, agent_id and workflow_id clearly. The description only restates the workflow/agent/status filters and adds no syntax, defaults, or interaction rules (for example what happens when both agent_id and workflow_id are supplied). Baseline 3 is appropriate when the schema does the heavy lifting.

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 the resource precisely ('Recent workflow and agent runs') and the ordering ('newest first'), which lets an agent distinguish it from run-detail siblings such as diagnose_run or list_run_files. The verb is only implied by the sentence fragment, and there is no explicit statement of what it does versus list_test_runs.

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?

Usage is implied by the word 'Recent' and by the 'optionally for one workflow, agent or status' filtering clause, so an agent can infer this is a filtered recent-runs listing. However, there is no explicit when-to-use versus alternatives, no mention of when to prefer a run-detail or diagnostic tool, and no exclusions.

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