read

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

Annotations already cover readOnly, idempotent, and non-destructive behavior, so the bar is lower. The description still earns credit for actionable traits beyond structured data: 1-based inclusive line ranges, images returned as images, and other binaries reported rather than returned. It omits error behavior (missing file, permission failures) and encoding concerns, so not a 5.

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 dense sentences with zero waste. The core purpose and line range are front-loaded, and the edge-case behavior for images and binaries follows without filler or repetition of annotation data.

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 three-parameter, fully annotated read tool with no output schema, the description covers the important decision points: what is returned for text, images, and other binaries. Missing error conditions and file-size or encoding caveats are real but minor gaps, so it falls just short of 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 100%, so the schema already documents path, start_line, and end_line including 1-based indexing and defaults. The description mostly restates the range semantics and adds context about non-text inputs rather than deepening parameter behavior, which matches the baseline 3 for high schema coverage.

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 gives a specific verb and resource ('Read a text file') and sharpens it with line-slicing and non-text handling. It is clearly distinguishable in spirit from list/search/stat, but it never names those siblings or states the contrast explicitly, which keeps it at 4 rather than 5.

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 use case (fetch file contents, optionally a line window) is implied clearly enough to act on. However, there is no explicit guidance on when to prefer this over stat, list, or search, and no stated prerequisites or exclusions, so it remains implied usage rather than real routing guidance.

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