Check Proton Bridge

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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint, so the safety profile is covered. The description adds valuable behavior beyond annotations by listing concrete failure conditions: Bridge not running, wrong IMAP port, and rejected stored credentials, plus the consequence of confusing a config fault with an empty inbox.

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 sentences, each earning its place: purpose and output, usage guidance, and failure behavior. It is front-loaded with the core action and immediately contrasts itself with siblings, with no filler.

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 zero-parameter read-only status tool with rich annotations and an output schema, the description is complete. It covers what the tool returns, when to call it, how it differs from siblings, and what error modes to expect.

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 tool has zero parameters and the schema covers 100% of them, so there is little for the description to add on parameter meaning. Baseline for zero-parameter tools is 4; the description instead clarifies output semantics, which is the more relevant information here.

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 names a specific action ('Check the local Proton Bridge connection'), a specific resource (the configured account), and the key outputs (INBOX message and unread counts). It also distinguishes itself from sibling tools by stating that this tool reports INBOX totals only, unlike list_folders and list_messages.

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 when-to-use guidance: call it first to confirm mail reachability, and before reporting the mailbox as unavailable. It also names which sibling tools to use for other needs, making the decision boundary clear.

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