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

Annotations already declare readOnlyHint=true and openWorldHint=false, so the bar is lower, but the description still adds real behavior: the tool returns instructional text that the agent is expected to follow, and the same content is mirrored as an MCP resource. That is meaningful context beyond the safety profile.

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 sentences, front-loaded with what the tool does, then the invocation rule. Every clause earns its place, with no restating of the schema or annotations.

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 tool with no output schema, the description covers what it returns (task instructions), how to use the result (follow it), when to call it, and the equivalent resource path. Nothing an agent needs to invoke it 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% with a 25-value enum, so the baseline is 3, but the description adds discovery context by noting that the server instructions enumerate the available skills. That helps the agent pick a valid enum value rather than guessing at the list.

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 and resource ('Load a Gamebeast skill') and clarifies what a skill is ('detailed instructions for a task') with concrete examples (insight queries, experiment data). It does not explicitly distinguish itself from doc-reading siblings like read_doc or search_docs, which an agent might plausibly confuse it with.

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 a clear trigger: 'Call this before a task a skill covers', and points to server instructions as the authoritative list. It also names an alternative access path (the skill://<name>/SKILL.md resource). No explicit when-not-to-use case is given, but the pre-task condition is a strong, actionable rule.

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