xray_scan

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

Annotations already declare read-only and closed-world behavior. The description adds that the tool builds a persistent architecture model, implying a session-level side effect, and the timing guidance suggests it may be resource-intensive. No contradictions with annotations.

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 sentences, front-loading the action and then adding usage timing. Every word is purposeful, with no redundancy or filler.

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 zero-parameter, read-only tool, the description covers its function and when to run it. It lists model components, providing a clear expectation of output, though it doesn't specify how the model is accessed or returned.

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 tool has zero parameters, so schema coverage is trivially 100%. The description adds context about what the scan covers, which indirectly helps the agent understand the tool's scope, though parameter detail is unnecessary.

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 action ('Scan the repository') and resource ('architecture model'), enumerating specific components like routes, entities, tasks, dependency graph, and findings. This differentiates it from sibling tools that summarize or generate diagrams.

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 explicit usage timing: 'Run once at session start and after structural changes.' It does not name alternatives or exclusions, but the context as a prerequisite scan is clear.

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