history

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

With no annotations, the description carries the full burden of behavioral disclosure. It reveals the return chain ordering (root first), each entry's shape, the special meaning of `origin: "editor"`, and the non-obvious instruction not to prefer the newest revision. This is rich behavioral context well beyond a simple one-liner.

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, each earning its place: the first defines the operation and output ordering, the second documents the entry fields and important origin marker, and the third gives usage guidance and a critical behavioral guardrail. The most important information is front-loaded.

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?

Since there is no output schema, the description supplies the return shape, field semantics, and the intended post-rewind workflow. It does not explicitly state that the operation is read-only or what identifies the root (e.g., null parent), but for a history-walk tool these are minor omissions and the agent has enough to invoke it correctly.

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 only defines `revision` as a required string with 0% coverage, so the description must compensate. It does explain that `revision` is the starting point for the walk and references it indirectly via `parent`, but it never clarifies the expected format, source, or valid values for the revision identifier. It adds some meaning but leaves a meaningful gap.

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 states a specific verb ('walk back'), a resource ('revision chain'), and a clear output scope ('root first'). It also distinguishes the tool's role from related siblings like edit and changes by framing it as a re-grounding step rather than a mutation or listing operation.

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 gives an explicit when-to-use: 'Use this to re-ground after a rewind' and a clear behavioral rule: 'Continue a prior design only when the user asked for it — never because it is the newest entry.' However, it does not name alternative sibling tools or explicitly state when not to use history in favor of another tool like changes.

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