Compare Market Periods

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

Annotations already declare read-only, idempotent, and non-destructive behavior. The description adds a meaningful behavioral trait with 'Does not assert causation,' which is a caveat about interpretation. It also specifies the output scope (aggregate statistics) without contradicting 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?

Two sentences with zero redundancy. The purpose is front-loaded, followed by output specifics and a caveat. Every sentence earns its place without fluff.

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 output schema exists and annotations cover safety, the description is complete. It specifies the timezone (America/Edmonton), the output categories (averages, min/max/median, load stats, deltas), and the no-causation caveat. Nothing an agent needs to call it correctly 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 description coverage is 100% — the request object's description mirrors the tool's purpose. The description does not add parameter-specific semantics beyond what the schema provides (e.g., date-time formats, required fields). Baseline 3 is appropriate because the schema handles the documentation.

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 states a specific verb ('compares'), resource ('aggregate pool-price and load statistics'), and scope ('two America/Edmonton market periods'). It clearly distinguishes itself from sibling tools like get_pool_prices or get_load, which are single-period queries, by focusing on comparison and deltas.

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 usage scenario is implied: it is for comparing two periods, as opposed to retrieving a single metric. However, the description does not explicitly state when to use this tool versus alternatives, nor does it list exclusions or prerequisites. No guidance is given about edge cases like overlapping periods or data availability.

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