derivation_delete_step

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

With no annotations, the description carries the full safety burden. It discloses the critical limitation (only the last step can be deleted) and implies destructiveness via 'deleting'. However, it does not explicitly state that deletion is irreversible or that an active session is required, though the example hints at the return format.

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 focused and well-structured. The warning box highlights the constraint, the Args/Returns/Example sections are concise and clear, and there is no filler. Every element earns its place.

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 simple delete-step tool, the description provides the essential constraint and an example return. The existing output schema covers return format details. However, the lack of any mention of session_id, even though it is an input parameter, prevents a perfect score.

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. It explains step_number as 'must be the last step', adding critical meaning beyond the schema. However, session_id is completely undocumented in both the description and schema, leaving half the parameters underspecified.

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 '刪除單一步驟' (delete a single step), a specific verb+resource pairing. It further distinguishes itself from siblings by stating '只能刪除最後一步' (can only delete the last step) and referencing derivation_rollback for intermediate steps, making the tool's unique role clear.

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 states when to use this tool (deleting the last step), and when not to (deleting intermediate steps), naming the exact alternative tool (derivation_rollback). This provides unambiguous selection guidance.

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