fetch_file

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

With no annotations provided, the description carries the burden of behavioral disclosure. It explains that JSON files are returned as parsed objects while other files are returned as strings, and it gives path conventions with examples. This is a useful behavioral trait beyond the bare schema. It does not mention error handling, but for a simple fetch tool this is reasonably transparent.

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 well-structured, with a one-sentence summary followed by Args and Returns sections. Every sentence adds value: the purpose, the format behavior, the parameter explanation, and the return type. No fluff or repetition.

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?

Given the simple one-parameter tool with no output schema, the description covers the essential aspects: what it does, how the path works, and what the return type is. It lacks error behavior or file size limits, but these are not critical for a straightforward fetch operation. The explanation of parsed JSON vs string return is particularly useful.

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 schema provides only the parameter name and type with no description (0% coverage). The description fully compensates by explaining that 'path' is relative to the server root and provides concrete examples like 'json/solar_regions.json'. This adds significant meaning beyond the raw 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 clearly states 'Fetch the content of a file from the SWPC data server', which is a specific verb+resource. It distinguishes itself from siblings like list_directory and describe_product by focusing on retrieving raw file content rather than metadata or listings.

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 implicitly communicates when to use it: whenever you need the contents of a specific file. The context is clear from the verb 'Fetch' and the path parameter. It doesn't explicitly mention alternatives, but the purpose is distinct enough that no exclusions are needed.

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