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

With no annotations provided, the description carries full burden. It discloses that the preview is 'no-data' and 'free', and lists excluded input types (GitHub handles, generated memories, mappings, file content). However, it does not describe side effects, return format, or safety profile (e.g., read-only nature), leaving gaps for the agent.

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?

Two sentences, front-loaded with the main purpose. The second sentence lists constraints succinctly without fluff. Every word contributes to clarity.

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, the description covers main purpose and constraints, but lacks details on what the preview returns or how it differs from preview_move. Since there is no output schema, the agent is left without expectations for the result. It is adequate but not fully 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?

The schema already covers the 'to' parameter with examples. The description adds value by mentioning '13 supported tools' and directing the agent to 'Use list_targets for the full matrix', which enriches the parameter semantics beyond the schema.

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 the tool's function: a free preview for building a user's first setup across 13 supported tools. It distinguishes itself from sibling preview_move by specifying 'first setup', though it does not explicitly compare with that sibling.

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?

It implies usage for previewing a first setup and mentions what inputs are not accepted, but does not explicitly state when to use this tool over alternatives like preview_move or start_checkout. The 'does not accept' clause gives some constraint guidance but not a clear when-to-use vs when-not-to-use.

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