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

Beyond the readOnly/idempotent annotations, the description reveals that an in-progress plan reports pending with a retry delay and that task ids are stable. This adds meaningful behavioral context about polling and revision handling that the annotations do not convey.

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?

Three sentences with dense, relevant information and no filler. The core read action is front-loaded, followed by lifecycle guidance and the non-mutating guarantee.

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?

With an output schema present, annotations covering safety, and one simple parameter, the description covers all operational essentials: what the plan contains, the pending state, polling guidance, and revision usage. Nothing needed for correct invocation is missing.

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 0%, so the description must compensate for the single planId parameter. It adds that the plan must be owned and that the tool should be polled after create_study_plan, which implies where the ID comes from. The schema pattern provides format, and the description provides enough operational semantics for one parameter.

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 uses a specific verb ('Reads') and a specific resource ('one owned study plan'), and lists the key contents ('stable task ids, completion state and revision'). This clearly distinguishes it from list_my_study_plans and create_study_plan.

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 explicitly tells agents to poll this tool after create_study_plan instead of creating again, and to use the returned revision for task changes. It also clarifies that reading older plans never changes them, giving both when-to-use and when-not-to-use guidance.

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