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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, covering the safety profile. The description adds a useful behavioral note that write replays return their original snapshot rather than current state, which isn't evident from annotations. No output schema exists, so return-shape detail is thin.

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?

Two compact sentences, front-loaded with the returned state then the replay caveat. No filler. Slightly dense but every clause carries return-value 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?

With no input params and no output schema, the description must carry the full burden of describing the return shape; it does so reasonably but the field list is a bare enumeration with no types or semantics. It also leaves ambiguity against confirm/delete/set notifications siblings unaddressed.

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?

Zero parameters means the baseline is 4. The description usefully describes what the response contains (channels, recovery availability, pending email changes, required proofs, expiry, resend time, next steps), compensating for the absence of an output schema.

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+resource ('Read current channels, recovery availability...') and enumerates the exact fields returned, which distinguishes it from generic read siblings. However, it doesn't distinguish it from confirm_notifications or delete_notifications explicitly, which would elevate it to a 5.

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?

It clarifies that write replays return their original snapshot and that this operation is for current state, implying when to use it. But with siblings like confirm_notifications, delete_notifications, and set_notifications, it doesn't say when to pick this over those alternatives.

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