test_connection

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

With no annotations provided, the description carries the full burden and does disclose the key behavioral trait: it exercises authenticated IMAP and SMTP paths but explicitly does not read or send mail, so it is side-effect free. It does not address what happens on partial failure (IMAP ok, SMTP down), timeouts, or whether stored credentials are required.

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?

One sentence, front-loaded with the action and scope, with the side-effect guarantee trailing it. There is no filler, hedging, or restatement of the tool name.

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 no-argument diagnostic with an output schema that already describes return values, the description supplies purpose and safety profile adequately. A minor gap is that it does not say whether both protocols are tested together or how a partial result is reported.

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 takes zero parameters and the schema is empty, so there are no parameter semantics to clarify; the baseline for a 0-param tool is 4. Nothing in the description contradicts or misrepresents the 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?

The description gives a specific verb+resource ("Test authenticated IMAP and SMTP connectivity") and adds a scope constraint, "without reading or sending mail," which separates it from mail-operation siblings like get_message and send_message. It does not explicitly name an alternative diagnostic sibling such as account_status or capabilities, so it falls short of the 5 benchmark.

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?

Usage is only implied: an agent can infer this is the right tool when it wants to validate credentials/server reachability with no side effects. The description never states when to prefer this over account_status or capabilities, nor any preconditions, so guidance stays at the implied level.

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