fetch_resource

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

No annotations are provided, so the description carries the burden. It discloses the fallback nature and URI format constraint, but doesn't describe what happens on invalid URIs, error behavior, or return format. The output schema exists, so return values are partially covered, but behavioral details like failure modes are missing.

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 compact and front-loaded with the fallback warning, then the URI format. It is slightly repetitive with the IMPORTANT emphasis, but every sentence earns its place. Could be trimmed slightly but overall efficient.

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 tool with an output schema, the description covers the key context: when to use, URI format, and where resource URIs come from. It lacks error-handling details and examples, but given the simplicity and output schema, it is reasonably complete.

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 0%, and the description only explains the URI format (resource://skillz/{skill-slug}/{path}) but does not explain what the resource_uri parameter represents beyond that. It adds some meaning but leaves the parameter semantics incomplete—no examples or clarification of path components.

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 clearly states the tool fetches a skill resource by URI, with a specific verb and resource. It distinguishes itself from siblings by emphasizing it is a fallback for clients without native MCP resource fetching, though it doesn't explicitly contrast with load_skill/read_skill_file/list_skill_files.

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?

The description explicitly says when to use this tool (only if client does NOT support native MCP resource fetching) and when not to use it (use native mechanism instead). It also specifies the URI format, giving clear usage context.

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