list_processes

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

With no annotations provided, the description carries the full burden, and it explicitly discloses that the operation is read-only, that it classifies by prototype chain, and that it never instantiates a process. This goes beyond the basic 'list' phrasing and gives meaningful behavioral assurance.

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 sentences: the first states the purpose and output, the second adds behavioral detail. There is no filler, and the most important information is front-loaded.

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, read-only listing tool with no output schema, the description is complete. It explains what is listed, the output format, examples, and the internal method, which gives an agent everything needed to invoke and interpret the tool correctly.

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 has zero parameters and an empty input schema, so the description does not need to explain parameter meanings. The description adds useful context about what the returned names represent, which is sufficient for a no-parameter tool.

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 states the exact action ('List every PixInsight process available on this installation') and the output format ('PJSR constructor name'), with concrete examples like 'SCNR' and 'PixelMath'. This clearly distinguishes it from sibling tools such as list_open_images or describe_process, which operate on different resources.

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 makes it clear that this tool is for enumerating all installed processes, which is a distinct use case. It does not explicitly name alternative tools or exclusion criteria, but the context and scope are clear enough for an agent to select it when needing the full process list.

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