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

Annotations already establish read-only, idempotent, non-destructive behavior, so the bar is lower. The description adds the crucial behavioral fact that the tool is deprecated and what the return contains (status, score, readiness), but says nothing about auth, rate limits, or how long deprecated access persists.

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 sentences with zero waste; the deprecation warning is front-loaded so an agent reads the most consequential fact first.

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?

With no output schema, the description usefully summarizes the returned fields and the migration path. For a single-parameter read tool, that is nearly complete, though it stops short of describing the exact response shape.

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?

Only one parameter (scanId) and schema description coverage is 100%, so the schema already documents its origin ('Scan id from scan_site.'). The description adds nothing about parameter format, and per the baseline rule a 3 is correct.

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?

States a specific verb and resource plus the fields returned: 'Reads one scan's status, score, and readiness.' It also names the replacement tool (get_report), which distinguishes it from siblings, though the differentiation comes from deprecation rather than scope.

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?

Explicitly tells the agent when NOT to use this tool ('Deprecated: use get_report'), naming the alternative. For routing purposes this is as clear as guidance gets.

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