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

Beyond the annotations (openWorld, non-idempotent, non-destructive), it discloses two non-obvious behaviors: it actually performs a real login across the network and the agent pins the server fingerprint on first login. It does not say what happens on a fingerprint mismatch afterward or whether failures come back as a result payload versus an error.

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 short sentences, front-loaded with the action and followed immediately by the return value and the fingerprint caveat. No filler or redundant restatement of the title.

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 two-parameter, open-world, non-idempotent operation with no output schema, the description covers what it does and roughly what it returns, which is the minimum viable level. It leaves out prerequisites, failure/mismatch semantics, and any indication of cost or latency of a real login attempt.

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 coverage is only 50%: agent_id is well documented (pattern plus pointer to get_account), but alias has no schema description at all. The phrase 'one of its servers' only weakly implies alias names a previously added server, and adds nothing about the 40-character limit or accepted format.

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?

Uses a concrete verb-and-resource framing: it makes an agent log into one of its servers and reports the outcome plus the server fingerprint. That is clearly distinct from add_machine/remove_machine/list_machines, though the description never names a sibling to contrast with explicitly.

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 would infer this is for verifying that an agent can actually authenticate to a server (e.g., after add_machine or before running duties). There is no explicit when-to-use, when-not-to-use, or prerequisite statement such as the server needing to exist or credentials being configured.

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