read_changes

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

Annotations already establish readOnly/destructive=false and closed-world, so the safety profile is covered. The description adds genuinely new behavior: an automatic full-sync fallback when the cursor is absent or expired, and the contract that each caller must persist the returned cursor itself. This cursor lifecycle detail is real value beyond the annotations.

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?

Three short clauses, front-loaded with the core action, then the fallback rule, then the cursor-persistence contract. No filler; each clause carries distinct information.

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 read-only tool with annotations covering the safety profile and no output schema, the description covers the essential contract (cursor input, full-sync fallback, returned-cursor ownership). The only gap is the unexplained 'format' option, which is minor.

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 0%, so the description must compensate. It partially does: it explains that the cursor is optional and what its absence/expiry means, which clarifies the cursor parameter. However, the 'format' parameter (text/json) is never mentioned, and the nested Cursor fields (session, seq) remain undocumented.

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 and resource — read the changes that occurred after a given cursor — which is unambiguous. It does not reference or differentiate itself from the siblings (observe_state, health, project_cell), but the resource is distinctive enough that differentiation is largely implicit.

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 explains the fallback condition (no cursor or an expired cursor triggers a full sync), which implies when the tool is usable, but it never states when to prefer this tool over the siblings or what a caller should do to trigger incremental vs full reads. Usage is implied rather than directed.

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