scan_diff

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

With no annotations provided, the description carries the full burden. It discloses that the tool 'only analyzes changed files and lines,' which is useful behavioral context about its scope. However, it doesn't mention performance characteristics (e.g., speed, resource usage), error handling, or what constitutes 'code quality issues,' leaving gaps in behavioral understanding.

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 two concise sentences with zero waste. The first sentence states the core purpose, and the second adds crucial context about scope and ideal use case. Every word earns its place, and information is front-loaded effectively.

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 no annotations and no output schema, the description provides adequate purpose and usage context but lacks details on what the tool returns (e.g., issue list format, severity levels) or behavioral traits like error conditions. For a tool with 4 parameters and no structured output documentation, this leaves room for improvement in completeness.

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 all parameters thoroughly. The description adds no additional parameter semantics beyond what's in the schema (e.g., it doesn't explain what 'SLA level' means or provide examples for 'path'). Baseline 3 is appropriate when the schema does the heavy lifting.

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's purpose with a specific verb ('scan'), resource ('git diff between two branches'), and target ('for code quality issues'). It distinguishes from sibling tools like 'scan_directory' by specifying it only analyzes changed files and lines, making it ideal for PR/MR review contexts.

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 for when to use this tool ('Ideal for PR/MR review') and specifies it 'only analyzes changed files and lines,' which implicitly differentiates it from 'scan_directory' that likely scans entire directories. However, it doesn't explicitly state when not to use it or name alternatives like 'explain_issue' or 'heal_code' for related tasks.

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