count_lines_of_code

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

With no annotations, the description carries the full behavioral transparency burden. It discloses key behaviors: counting total lines, distinguishing code from non-code lines, and grouping by file extension. This is clear, though it does not address performance, recursion depth, or handling of binary files, but for a line-counting tool this is adequate.

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 very concise, front-loaded with the main purpose in the first sentence, and uses only two sentences. Every word contributes meaning without redundancy.

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?

The tool has a moderate complexity with three optional parameters, full schema coverage, and an output schema. The description sufficiently explains the tool's scope and output granularity. It does not detail the return format, but the presence of an output schema and the simple nature of the tool make this acceptable.

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 input schema provides 100% coverage with detailed descriptions and defaults for all three parameters. The description adds no additional parameter semantics beyond what the schema already offers, so the baseline score of 3 applies.

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 uses a specific verb and resource: 'Count lines of code across the codebase.' It clearly states what is counted (total, code, blank, comment lines) per file extension, which distinguishes it from other file-analysis tools like search_files or analyze_project.

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 indicates when to use this tool (when line counts are needed), but it does not explicitly state when to use it over alternatives or mention any exclusions. No alternative tools are named, so usage guidance remains implied rather than explicit.

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