List ARexx ports

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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, closed-world), and the description's "Read-only" simply restates that. It does add value beyond annotations by disclosing the output shape ("one name per line") and the semantics of what appears in the list, which is the key behavioral detail for this tool.

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?

Short and front-loaded, with the core action in the first clause. The middle sentence is somewhat wordy and the final "Read-only" duplicates the annotations, but neither is costly at this length.

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 zero-parameter listing tool with no output schema, the description supplies the essential return format and the meaning of the entries. It does not mention empty-result behavior or whether the list can be large, but nothing critical to invoking it is missing.

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 tool takes zero parameters, so the baseline is 4. The description correctly avoids inventing filter arguments and implies the listing is unfiltered and global.

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 a specific verb and resource ("List the public message ports") and explains that scriptable programs appear under their port names. The trailing "for amiga_arexx" hints at how the result is consumed but is too terse to sharply differentiate it from the amiga_arexx and amiga_rexx siblings.

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?

Usage is only implied: an agent can infer this is the discovery step that produces port names to feed into amiga_arexx, but no explicit when-to-use or when-not-to-use guidance is stated. No alternative tool is named.

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