read_file

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It goes beyond a simple summary by explaining the raw text return format, the rationale against JSON wrapping, truncation policy for long files, and how continuation after truncation is reported. It also explicitly states the operation is read-only.

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 core purpose. Every sentence earns its place: raw output format, truncation behavior, and read-only status. It is neither padded nor under-specified.

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 relatively simple file-reading tool with an output schema present, the description covers the most important behavioral concerns: raw text, truncation, continuation, and read-only safety. However, it omits parameter-level semantics and explicit routing among siblings, so it is not fully 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%, so the description must compensate for explaining path, max_lines, and start_line. It does not describe any of these parameters explicitly, and while it mentions truncation, it never ties that behavior to the max_lines parameter or explains how start_line and max_lines interact. Parameter names and defaults exist in the schema, but the description adds no semantic guidance.

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 opens with a specific verb and resource: 'Read a UTF-8 text file.' It clearly distinguishes this from siblings like write_file, edit_file, list_directory, and find_files by establishing the read-only nature and the target content type. There is no ambiguity about what the tool accomplishes.

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 provides clear context: this is the tool for reading text files and is explicitly read-only, which implies it should not be used for writing or editing. However, it does not explicitly name alternatives or provide when-not-to-use guidance, so it stops short of a 5.

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