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

Beyond the readOnlyHint/openWorldHint annotations, the description discloses what comes back: an A–F grade, a one-sentence user-facing summary, a recommendation from a fixed set of five values, warning signs, and a report link. That is real value for a tool with no output schema, especially the enumerated recommendation vocabulary. It omits operational context such as rate limits, latency, or whether private repos are handled differently.

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?

Three sentences, each doing distinct work: purpose, trigger conditions, and return payload. The action-relevant purpose is front-loaded and the return-value list is compact rather than prose-heavy. No filler or repeated framing.

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 single-parameter, read-only tool with no output schema, the description covers purpose, trigger conditions, supported scope, and expected return fields including the recommendation enum. An agent could decide to call it and interpret the response without further documentation.

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 description coverage is 100% for the single `repo` parameter, and the schema already shows both accepted forms (URL or owner/name). The description adds only the scope constraint "works for any public repo," which is useful but not a syntax or format clarification. Baseline 3 is appropriate when the schema carries the parameter detail.

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 first sentence states a specific verb and resource with scope: "Check whether a GitHub repo is safe before installing, cloning or running it." That is far more than a restatement of the name, and the domain (GitHub repo safety) is clearly distinct from the post/scheduling siblings. It stops short of a 5 because it never addresses the nearest-sounding sibling, get_safety_scores, leaving the agent to infer the boundary from names alone.

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?

Provides concrete triggering conditions: call it whenever the user shares a GitHub link, or asks to install a tool, app, MCP server, Claude skill or plugin from GitHub. That covers a wide range of realistic prompts. It gives no explicit when-not or prerequisite guidance (e.g. private repos, non-GitHub sources) and names no alternative tool.

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