Companion Result

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

With no annotations, the description carries the transparency burden. It clearly states this is a 'Read' operation, implying non-destructive behavior, and lists the data fields it returns. However, it does not disclose whether reading consumes the result, what happens when no result exists, or any other side effects.

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 a single, front-loaded sentence with no redundant words. It packs the action, the three types of data returned, and the scoping context into exactly 12 words, making it highly concise and well-structured.

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 one-parameter read tool, the description lists the return fields (result, resume command, session metadata) but omits edge cases like empty results or default cwd behavior. No output schema or annotations exist to provide additional context, so the description is only minimally 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 only parameter, cwd, is given semantic meaning through 'for a cwd', indicating it is the working directory context. However, the description does not clarify whether cwd is optional, what default is applied, or the expected path format, leaving some ambiguity.

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 uses the specific verb 'Read' and identifies the exact resources: 'latest companion result, resume command, and session metadata' scoped to 'a cwd'. It is clear and likely distinguishes from sibling tools, though it does not explicitly name alternatives.

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?

No guidance is provided on when to use this tool versus companion_recent, companion_status, or companion_resume. There is no mention of preconditions, such as having run a companion command first, or when another tool would be more appropriate.

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