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

The annotations already declare read-only, idempotent, and non-destructive behavior, and the description's 'Read-only' simply repeats that. The description adds a scope qualifier ('compatible agent hosts') but does not describe response shape, errors, or availability, so it meets the lower bar set by the annotations without exceeding it.

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?

The description is concise and front-loaded, with the main action in the first sentence. The second sentence, 'Read-only,' is slightly redundant with the annotations, but it is short and reinforces safe invocation rather than adding significant clutter.

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?

This is a simple zero-parameter, read-only tool with rich annotations, so little additional context is required to invoke it safely. Because there is no output schema, a slightly more concrete description of what 'protocol connection information' includes would improve completeness, but the current description is adequate for selection and invocation.

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 input schema has zero parameters and 100% schema description coverage, so there is no parameter meaning for the description to supply. The baseline of 4 applies because there is nothing for the description to add beyond the empty 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 states a clear verb and resource: it returns protocol connection information for compatible agent hosts, which is distinct from the sibling capability-related tools. It is specific enough to select, though 'compatible agent hosts' is left somewhat vague and the description does not explicitly contrast it with the sibling tools.

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?

No guidance is provided for when to use this tool versus list_evercraft_capabilities or match_evercraft_capability. 'Read-only' is a safety signal, not a usage condition, so an agent must infer the appropriate context from the tool name and description alone.

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