detect_phases

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

With no annotations, the description fully carries the burden. It transparently describes the analysis (full history, trend direction, caloric balance) and outputs (duration, weight change, deficit/surplus). No contradictions.

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 concise: two sentences in the main body plus a clear args section. No redundant or unnecessary information. Every sentence earns its place.

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 the tool's simplicity (one optional parameter) and presence of an output schema, the description adequately covers what the tool does and what it returns. Missing edge cases but appropriate for the complexity.

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 only parameter (min_days) has a default of 14. The description explains its purpose: 'Minimum days for a phase to be reported.' This adds value beyond the schema, which has empty descriptions (0% 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: 'Auto-detect cut/bulk/maintenance phases from weight trend and energy balance.' It uses specific verb ('auto-detect') and resource ('phases'), distinguishing it from siblings like body_comp_trend or get_weight_trend.

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 implies usage for phase detection by mentioning analysis of full history, but it does not explicitly state when to use this tool over alternatives like get_insights or get_weight_trend. No exclusion criteria or prerequisites are mentioned.

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