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

With no annotations provided, the description carries full burden. It discloses the core logic (day-ahead prices, green scores, optimization modes, ranked list) but misses behavioral details like read-only nature, handling of missing data, or exact ranking/tie-break behavior.

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, front-loaded with purpose, zero fluff. Every clause earns its place while covering the essential inputs, methodology, and output type.

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?

No output schema and no annotations; description says 'ranked list' but doesn't clarify whether the list ranks zones or hour blocks, nor what fields appear in each item. It also doesn't mention behavior when no valid block exists. Missing these details hurts 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 baseline is 3. The description adds little beyond the schema; 'contiguous' and 'UTC deadline' are already in the schema. It does clarify the optimization intent but not significantly.

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 a specific verb+resource: 'find the best contiguous hour block before a UTC deadline' across multiple zones. It also distinguishes itself from siblings like get_cheapest_window by supporting multiple optimization modes (price, carbon, balanced).

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 gives a clear use case: 'where flexible compute or charging could run' and 'before a UTC deadline'. It does not explicitly mention alternatives or when not to use, but the context is clear enough.

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