echo

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

Annotations already declare readOnlyHint=true, so the description does not repeat that. It adds useful context about returning JSON by default and the --raw option, but does not detail all behaviors like encoding or escape handling, which are covered in the schema.

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 two concise sentences, front-loaded with the core purpose and side effects, and includes a clear note about alternative tool. Every sentence adds value.

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?

Given 8 parameters and no output schema, the description covers the main behavior (echo text as JSON) and key variant (--raw). It mentions no side effects and sibling tool. The schema covers the rest, so the description is sufficiently complete for an agent to decide usage.

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 only adds context for the 'raw' parameter (plain text vs JSON) but does not elaborate on other parameters, which are already described in 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?

Description clearly states the tool outputs provided text as JSON, distinguishes itself from sibling 'printf' by specifying it is not for formatted output. It also mentions the default JSON envelope and --raw flag for plain text.

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?

Explicitly tells when to use: to display values or construct output strings in agent pipelines. Also tells when not to use: for formatted output, recommending 'printf' instead.

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