list_sessions

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

Annotations provide readOnlyHint=true, which the description doesn't contradict. The description adds valuable behavioral context beyond annotations: it explains what status information is shown (PID, Blocked, Runtime), provides debugging guidance for interpreting 'Blocked: true', and mentions potential stuck process scenarios. This goes beyond the basic read-only annotation.

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 appropriately sized but has some structural issues. The first section clearly states the purpose, but the 'DEBUGGING REPLs' section could be more integrated. The final sentence about command referencing feels somewhat disconnected from the core functionality description.

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 this is a read-only tool with no parameters and no output schema, the description provides good context about what information is returned and how to interpret it. It covers the tool's purpose, usage scenarios, and output interpretation adequately for its complexity level.

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?

With 0 parameters and 100% schema description coverage, the baseline would be 4. The description appropriately doesn't discuss parameters since none exist, and instead focuses on what the tool returns and how to interpret the output.

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 specific action ('List all active terminal sessions') and resource ('terminal sessions'), distinguishing it from sibling tools like list_processes or list_directory. The title annotation 'List Terminal Sessions' reinforces this, but the description provides the full verb+resource combination.

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 provides clear context for when to use this tool ('to verify sessions are running before sending input' and debugging REPLs), but doesn't explicitly state when NOT to use it or name specific alternatives. It distinguishes from siblings by focusing on terminal sessions rather than processes or directories.

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