Read Text File

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

Annotations already declare readOnlyHint=true and openWorldHint=false, and the description adds meaningful behavior: handling various text encodings, providing detailed error messages, supporting head/tail line limits, and restricting operation to allowed directories. These details go beyond the annotations without contradicting them.

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 moderately sized and front-loaded with the core purpose. Each sentence contributes useful information such as encoding handling, error messages, usage context, parameter behavior, and access restrictions. There is slight redundancy between the first sentence and the usage guidance, but it is not wasteful.

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 simple read-only tool with an output schema, the description covers essential context: encodings, error behavior, head/tail options, extension-agnostic text handling, and directory restrictions. It does not explicitly clarify the relationship with the sibling read_file tool or address potential interactions between head and tail, but these are minor gaps given the schema and annotations.

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 67%; the head and tail parameters are already described in the schema. The description reinforces their behavior and adds that the default is complete contents, but it does not add meaningful detail for the undocumented required path parameter beyond implying it is a file system path within allowed directories.

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 reads the complete contents of a file as text, which is a specific verb+resource. It distinguishes itself from read_media_file by specifying text regardless of extension and from read_multiple_files by focusing on a single file, but it does not explicitly differentiate from the similarly named sibling read_file.

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?

It explicitly says to use this tool when examining the contents of a single file, giving clear context. It implies exclusions through 'as text regardless of extension' and 'Only works within allowed directories,' but it does not name alternative tools such as read_media_file or read_multiple_files when those would be more appropriate.

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