tracker_session_diff

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

Annotations already indicate readOnly, idempotent, non-destructive behavior, so the description's job is to add behavioral context. It does this by describing the output nature: counts by action and entity plus notable changes. It does not contradict annotations and adds useful expectations beyond the structured metadata.

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 two sentences, front-loads the core purpose, and includes a practical usage pointer. Every sentence earns its place with no wasted words.

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 read-only tool with one parameter and no output schema, the description is sufficiently complete: it states what is returned, when to call it, and the time-based input. It could optionally mention the timezone or that no nested data is returned, but neither is essential 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?

The input schema already describes the 'since' parameter with ISO 8601 format and an example, so description-level parameter detail is largely redundant. The description reinforces the meaning of 'since a timestamp,' but adds little beyond the schema, earning the baseline score for high schema coverage.

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 tool reports what changed since a timestamp, including counts by action and entity plus notable changes. It is understandable and consistent with the tool name, though it lacks an explicit verb like 'retrieve' and does not name a sibling to differentiate from.

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 gives explicit guidance: 'Call it at the start of a session to catch up.' This provides a clear when-to-use scenario, though it does not mention when not to use it or compare it to similar tools like activity_log or tracker_dashboard.

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