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

Annotations already flag destructiveHint=true and idempotentHint=true; the description earns credit by explaining what the destructive behavior actually looks like ('steps (set-replace array)', null to clear assigneeId/storyId, cross-project ids rejected) and what survives a suite move ('keeps its id, results and links'). It does not mention permissions, error shapes, or limits, which keeps it below 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?

Front-loaded with a complete field list in the first clause, then patch/null and validation rules. Dense parentheticals make the single run-on sentence heavier than ideal, but every clause carries actionable information.

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 an 11-parameter mutation with no output schema, the description covers field semantics, patch behavior, and the cross-project guard. The remaining gap is what the call returns and whether partial-failure is possible when both steps and suiteId change; minor, but not negligible for a destructive patch.

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 only 27%, and the description compensates fully: it gives the steps item shape ({ action, expected }), the nullable-clear semantics for three fields, the accepted storyId formats (ticket key or UUID), and the suiteId side effect of moving the case. This is meaning well beyond the raw schema.

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 and resource ('Patch fields on an existing test case') and immediately enumerates the mutable fields, so an agent can distinguish it from create_test_case, delete_test_case and update_test_suite without opening any schema.

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?

Clearly establishes patch semantics — 'Any omitted field is unchanged; pass null to clear assigneeId / storyId' — plus a constraint ('Cross-project ids are rejected') and a discovery pointer ('ids from stride.list_test_suites'). It stops short of naming sibling alternatives such as update_test_suite for suite-level changes, so exclusion guidance is implicit rather than explicit.

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