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

Annotations already declare readOnly/idempotent/non-destructive, so the safety profile is covered; the description still adds real behavior: data is sampled every minute, nothing is executed live, and the response shape changes based on whether `host` is supplied. It does not discuss auth requirements or rate limits, which keeps it short of a 5.

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?

Front-loaded with what is returned, then the two parameter behaviors, then the usage guidance. The metric enumeration is long but functional, and every sentence carries information; only mild tightening is possible.

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 output schema and only two optional parameters, the description supplies everything needed: the returned fields, the two response modes, the default for `hours`, and the coverage limitation for servers without metrics enabled. Nothing an agent needs to call this correctly is missing.

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 100%, so the baseline is 3, but the description goes further by explaining the semantic consequence of each parameter: omitting `host` yields one line per server, supplying it yields that server's full latest sample plus average and peak over `hours` (default 6). That is genuine added meaning beyond the schema's field-level text.

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: reads the metrics Termalin's monitoring already collects (CPU, memory, disk, load, network, processes, services, containers, certificates) from the user's servers. It explicitly distinguishes itself from the closest sibling by saying to reach for it 'before reaching for ssh_exec', so an agent can route correctly without opening either schema.

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?

Gives concrete when-to-use triggers ('how is the server doing', 'what happened at night') and names the alternative (ssh_exec) plus the boundary condition ('Covers servers with metrics switched on'). It also clarifies it does not run anything now, which rules out a plausible mis-selection.

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