rca_dtree_list_sessions

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

Annotations already mark the tool as read-only, idempotent, and non-destructive. The description adds valuable non-obvious behavior: free-plan keys receive a plan_required error instead of results, the resolved_only flag excludes in-progress sessions when true, and returned data includes status and diagnosis only when resolved.

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 well structured with a clear purpose statement, usage guidance, compact Args section, and Returns shape. It front-loads the main action and each section earns its place without unnecessary filler.

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?

The description gives everything an agent needs to decide to call this tool and interpret the response: session source, filtering, resolved status semantics, plan-gating behavior, returned JSON shape, and follow-up workflows with sibling tools. The output schema exists for structured return details, so the prose return description is a helpful supplement.

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 description summarizes the two meaningful parameters, equipment_id as an optional filter and resolved_only with its default false behavior. The input schema does describe these fields, so the description is partly redundant, but it also connects them to the return contract and expected session lifecycle. It omits token and client_id, though those are covered by 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?

The description clearly states the operation: 'List your equipment diagnostic sessions' and specifies the source ('started via rca_dtree_start') plus what each session contains ('status and diagnosis if resolved'). It differentiates this tool from the related workflow tools by explaining it produces session_id values for rca_guide_generate_report and rca_dtree_answer.

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 explicitly says when to use it: 'find a session_id for rca_guide_generate_report, check whether a session is already resolved before continuing it with rca_dtree_answer, or review diagnostic history.' This gives clear selection context and naturally excludes cases where another tool should be used.

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