Recent Thunderbird events

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

Annotations already declare readOnlyHint=true and idempotentHint=true. The description adds crucial behavioral context: the buffering nature, polling mechanics, and the risk of missing events during long gaps. This goes beyond annotations to explain how the tool behaves in practice.

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 sentences, each serving a purpose: purpose, usage hint, behavioral nuance. No wasted words. Front-loaded with key 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?

Given the presence of an output schema (which explains return values), the description covers the essential behavioral aspects: what events are included, how to poll incrementally, and the risk of buffer overflow. For a simple polling tool, this is complete.

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 description must compensate. It provides meaningful context for 'since' (used for incremental polling), but does not explicitly describe 'limit' beyond its default. The hint about 'since=latestSeq' is helpful, but both parameters could benefit from more explicit descriptions. Overall, adequate but not exceptional.

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?

Clearly states 'Read buffered Thunderbird notifications: new mail, folder and account changes.' This provides a specific verb (Read) and resource (buffered Thunderbird notifications), and lists examples differentiating it from sibling tools that deal with individual mail or folder operations.

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?

Explicitly describes polling pattern: 'Poll with `since=latestSeq` from the previous call to see only what is new.' Also warns about buffer size and how to detect dropped events ('`latestSeq` jumping by more than you received is how you tell'). This is excellent guidance.

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