ado_testcases_add_to_suite

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

The description discloses the required vso.test_write PAT scope and the static-suite-only restriction, which are operational behaviors that the agent must know before calling. While the annotations already signal a write operation (readOnlyHint=false) and open-world behavior, they don't disclose the permission or the static-vs-dynamic suite limitation, so the description adds meaningful value. It stops short of explaining partial failure behavior, which is why it's a 4 rather than 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?

Five short sentences, each carrying a distinct piece of information: what it adds, what the input must look like, how to create good input, which suite type it works on, and what scope it needs. No low-value filler or repetition of the schema it already would see. The action is front-loaded.

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 mutating tool with a write annotation, the description is complete enough: it states the action, expected input type, related creation workflow, valid suite type, and permission requirement. With no output schema, some descriptions would risk leaving the agent blind on return values, but here the operation is conceptually contained (adding memberships) and the prerequisites that an agent might not guess are all spelled out.

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?

The schema already documents all four parameters at 100% coverage, so the baseline is 3. The description adds genuinely useful semantic constraints: testCaseIds must be work item IDs of type 'Test Case' and the array caps at 100 per call, reinforcing the behavior. The suite must be static (suiteId alone doesn't convey that), which is additional semantic nuance that helps the agent pick a valid suite. This elevates it to a 4.

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 leads with the specific verb+resource ('Add existing Test Case work items to a suite') and clarifies that this is for existing test cases only. It also distinguishes itself from sibling tools by telling the agent to use ado_workitems_create for new test case creation, making it unambiguous against the surrounding tools.

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 gives an explicit prerequisite condition: use ad_workitems_create with type='Test Case' first if the items don't exist yet. It also defines a hard constraint – only works for staticTestSuite, whereas dynamicTestSuite membership is query-driven – so the agent knows exactly when to use or not use this tool without opening any schema.

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