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

No annotations are supplied, so the description carries the full burden. It helpfully discloses that the result is a 'latest probe' (implying a cached/stale snapshot rather than a live check) and what the payload contains, but says nothing about cost, rate limits, permission needs, or behavior on unknown/unregistered servers.

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 compact sentences with zero filler; the returned-field list comes first and the accepted identifier forms immediately after, so the essential information is front-loaded.

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 one-parameter, no-output-schema read tool this is nearly complete: the accepted identifier forms and the informal shape of the response are both covered. The only gap is the check_server overlap and any failure mode for unresolvable names.

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?

With a single parameter at 100% schema description coverage, the schema already documents nameOrUrl. The description adds the concrete name format 'io.github.owner/name' as an example and notes the URL alternative, which is modest but real added meaning over 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?

Specific verb+resource: retrieves the latest probe for exactly one registry server, and it enumerates the returned fields (status, protocol, tool count, token cost, latency). It implicitly separates itself from plural siblings like search_servers and registry_summary, but never names them 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 implied by 'one server' plus the accepted identifier format, but there is no explicit when-to-use guidance and nothing to disambiguate it from the near-synonymous check_server sibling (e.g., whether this reads a cached result while check_server runs a fresh probe).

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