session_list

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

With no annotations, the description carries full burden and discloses key behaviors: sessions expire ~10 min after last heartbeat, default scoping to the current project, fallback to organization if no project linked, and parameter interactions. No contradictions.

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 a moderate-length paragraph with key information front-loaded. Each sentence adds value, and there is no redundant or repetitive content. Could be slightly more concise, but overall efficient.

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 no output schema, the description provides sufficient context about behavior and parameter effects. It mentions that the tool shows 'what each is focused on,' hinting at output structure. For a listing tool, it covers the major aspects needed for correct invocation.

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% with individual parameter descriptions. The description adds extra semantics, such as explaining that `all_projects` is ignored when `project` is provided, which goes beyond the schema. It also clarifies default behavior for scoping.

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 starts with a specific verb and resource: "List OTHER live Claude Code sessions working on the same project right now, and what each is focused on." It clearly distinguishes from sibling tools like session_end and session_update, and no other tool lists live sessions.

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 states when to use the tool: "Use it at conversation start and before big changes to avoid stepping on parallel sessions." It also explains default scoping and fallback behavior. However, it does not explicitly mention when not to use it or contrast with alternatives.

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