get_real_savings

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

Annotations already declare readOnly, idempotent, and non-destructive hints, so the description does not need to repeat safety traits. It adds useful behavioral context by describing the exact return shape: files with raw_tokens, compact_tokens, savings, and total_savings. This is valuable because there is no output schema.

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 compact and front-loaded with the core purpose, then clearly differentiates the tool from a sibling, and finishes with the return JSON shape. Every sentence earns its place with no 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 simple read-only tool with one optional parameter, the description is complete: it explains what the tool does, when to use it, what it returns, and how it differs from the closest sibling. No important context is missing.

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 coverage is 100%, and the only parameter, period, is fully documented in the schema with an enum and default of 'week'. The description does not add parameter-level meaning beyond the schema, which is expected given high 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 clearly states the tool's purpose with a specific verb and resource: 'A/B comparison: how many tokens could be saved by using trace-mcp instead of raw Read/Bash file reads.' It also specifies the per-file breakdown, making it easy to distinguish from other reporting tools like get_optimization_report.

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 explicitly directs when to use this tool versus an alternative: 'For pattern-based waste detection use get_optimization_report instead.' This provides a clear exclusion and alternative, so an agent can route correctly without opening the schema.

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