list_recent_sessions

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

With no annotations, the description must carry the behavioral burden; it does disclose the return fields (session IDs, titles, working directories, turn counts, timestamps), which is genuine content. It never states that this is a read-only, non-mutating operation, nor anything about pagination or the semantics of 'recent'.

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?

A single front-loaded sentence with zero filler. Because there is no output schema, the enumeration of returned fields is load-bearing rather than redundant, and nothing could be cut without losing signal.

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 simple, zero-required-parameter list tool with no output schema, the description covers platforms and return fields adequately. The remaining gaps are the undefined 'recent' window and any pagination/ordering behavior, which an agent would want before relying on the result set.

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 description coverage is 100%, so all three parameters (cwd, agent, limit) are already documented in the schema. The description only obliquely echoes them via 'working directories' and the platform list; it adds no syntax, default, or format detail beyond what the schema provides, so the baseline 3 applies.

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?

States a specific verb (List) and resource (recent coding sessions) and enumerates the four platforms covered plus the fields returned, so the agent knows exactly what comes back. It does not, however, name or contrast itself with the sibling search_cross_agent_history, which is the tool most likely to be confused with a listing call.

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?

There is no when-to-use guidance, no exclusions, and no mention of when to prefer search_cross_agent_history or pull_handoff_context instead. The word 'recent' is the only scoping cue and is never defined (window, sort order, or relationship to the limit default of 15).

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