session_redo

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

With no annotations, the description carries the burden of disclosure. It adds the key behavioral trait that redo is only valid until a new cad() operation, and it describes the return format (JSON with restored step numbers). It does not elaborate on failure behavior when n exceeds available steps, but the core behavior is transparent.

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 extremely concise and well-structured. The first sentence delivers the primary purpose, followed by clear Args and Returns sections. No wasted words, and the layout aids quick comprehension.

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 one-parameter tool with an output schema, the description covers the essential use case, return format, and validity constraint. It lacks explicit error-handling notes or edge cases, but given the tool's simplicity, it is nearly complete.

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. The description fully explains the only parameter 'n' as 'Number of steps to restore (default 1)', providing complete semantic meaning beyond the schema's type and default.

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 clearly states a specific action with a specific resource: 'Redo n previously rolled-back steps'. It also adds a temporal constraint, 'valid until a new cad() operation', which helps distinguish this from other session operations. It effectively differentiates from sibling tools like session_rollback.

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 clear contextual usage: redo is for restoring previously rolled-back steps and is only valid until a new cad() operation. It implies when to use it without explicitly naming alternatives or exclusions, but the context is sufficient for an agent to decide.

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