diff_map

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

With no annotations, the description carries the full burden. It only says the tool compares snapshots, but it does not disclose whether the operation is read-only, what happens if no previous snapshot exists, or any side effects on the session. The information is minimal and leaves important behavior unknown.

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 single, concise sentence that directly states the tool's action. It is free of redundant information and skims the clause name of the tool, but it leans toward under-specification because it omits any behavioral or output details. The form is efficient, though length is short of the needed depth.

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 tool has a simple schema, but there is no explanation of what the diff result looks like (no output schema) or the relationship between target session and the snapshots being compared. The lease/session parameters are documented, but their impact on the mapping is unclear. The description does not cover the essential contextual gap, leaving an agent uncertain about return structure and operational assumptions.

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%, so the lease and session parameters are well documented in the input schema. The description adds no further meaning, not even clarifying how lease or session relate to the snapshots being diffed. This is a baseline 3, as the schema already handles the parameter descriptions and the description does not detract or add.

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 a specific action ('diff') on a defined resource ('current snapshot vs the previous one'). It distinguishes the tool from sibling tools like map and map_compact, which generate snapshots rather than compare them, though the term 'snapshot' is not elaborated.

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?

No guidance is given for when to use this tool versus alternatives, such as verify_map or expect. The description does not specify prerequisites, like the need for an existing snapshot or typical scenarios (e.g., comparing state before and after an action). Usage is only implied by the verb 'diff'.

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