expand

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

The description explicitly states 'Read-only, no side effects (does not modify files)', which aligns with the readOnlyHint annotation and adds details about output format (JSON envelope by default, raw with --raw) that go beyond annotations.

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 concise with five sentences, each serving a purpose: core function, read-only guarantee, output format, usage guidance, and alternative tool. Information is front-loaded and no sentence is wasted.

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?

With 8 parameters and no output schema, the description covers the main purpose, safety, and alternative tool. It does not detail all parameters, but the schema does. It could mention encoding options briefly, but the schema compensates.

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 coverage is 100%, so baseline is 3. The description adds context about configurable tab stops, raw mode, and default storage (stdin), which adds meaning beyond the schema's field descriptions.

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 converts tab characters to spaces in files or stdin, using the verb 'convert' and specifying the resource. It distinguishes from the sibling tool 'unexpand' by noting the reverse 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 explicitly tells when to use the tool (normalize indentation to spaces) and when not to (for converting spaces to tabs, use 'unexpand'). It also mentions reading from stdin vs files and the choice of JSON or raw output.

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