complete_contract

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

With no annotations, the description carries the full burden and does so excellently. It discloses strict validation behavior with structured rejection and detailed diffs (two failure types), idempotency (repeated calls return existing result without error or duplicate write), and the semantics of the completion_note as a serious testimony. It also explains the final-state nature, making the mutation's effects clear.

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?

The description is long but every sentence earns its place. It is front-loaded with the primary action, then systematically covers state distinction, note expectations, preconditions, failure modes, and idempotency. Numbered lists and clear separation of concerns make it easy to parse despite its density. No fluff or redundancy.

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?

This is a complex mutation tool with strict preconditions, failure modes, and idempotency behavior. The description covers all these aspects, references related tools (update_contract_coverage, get_context), describes rejection response structure, and explains the repeated-call behavior. No output schema exists, so the description sufficiently explains what to expect. It is effectively complete for an agent.

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 covers all parameters at 100%, so the baseline is 3. The description adds value by elaborating on completion_note's intent ('不是流程按钮上敷衍一句') and idempotency_key's use in retries ('网络重试/断线重连时带上同一个 key'), going beyond the schema's descriptions. However, it does not add significant new meaning for contract_id beyond the schema. Thus a 4 is appropriate.

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 opens with a clear, specific verb+resource: '把一份合约收作结业' (close a contract as completed). It distinguishes this from sibling tools like void_contract by explaining it is the third terminal state (completed_at/completion_note) alongside established/voided, and explicitly notes it is not an override relationship. This makes the tool's purpose unambiguous and well-differentiated.

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 provides explicit when-to-use and when-not-to-use guidance. It states preconditions required before calling (contract active, covered_course_ids non-empty, each course goal_completion_ready) and names alternative/upstream tools ('先 update_contract_coverage', '见 get_context 的 contract_progress'). It also clarifies that voided or already-terminal contracts are rejected, implicitly distinguishing from void_contract. This is comprehensive usage guidance.

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