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

Goes well beyond the annotations: it discloses that the updated plan replaces the previous one under a new proposalId, that nothing is launched until relaunch, that numTesters only changes via edits.audience.numTesters, and that launched-test edits are saved and echoed back as audience. This matches destructiveHint=true with concrete detail on what is replaced.

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-loads the core action and then branches cleanly into Draft vs Launched, so the branching is scannable. It is dense and a bit long, but nearly every clause encodes a constraint that would otherwise be missed.

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 4-param, deeply nested mutation tool with an output schema, the description supplies the operational rules an agent needs (which id, which edits allowed, launch state, replacement semantics). The only gap is the internal structure of edits.audience, which is neither in the schema descriptions nor the text.

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?

With 0% schema coverage the description must carry the load, and it explains all four top-level params (proposalId, projectId, changes, edits) plus the meaning of key edit sub-operations (add/remove tasks, questions, goals by index, swap personaIds). It does not, however, explain the many nested audience fields (voice, personality, age ranges), leaving that part of the deep schema unannotated.

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 (Edits) and resource (usability test) and immediately splits the operation into two precise modes keyed by proposalId vs projectId. An agent can distinguish this from propose_usability_test and relaunch_usability_test 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?

Explicitly states when to use proposalId (unlaunched draft) vs projectId (already-launched test), names relaunch_usability_test as the follow-up and notes tasks/questions/goals of a launched test cannot be edited and 'a new test is needed for that.' When-to-use, when-not-to, and the alternative are all present.

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