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

Annotations already declare readOnlyHint, idempotentHint and openWorldHint, so safety is covered. The description adds real value beyond them: result ordering ('newest drops first'), returned fields (from/to price, drop percentage), and cost ('One API request per call').

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?

Five short sentences, front-loaded with the core concept and return shape, then defaults, then tuning, then filters. No filler and every clause carries information.

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 and 8 parameters at 13% description coverage, the description does most of the necessary work: what the signal is, ordering, returned fields, defaults and filter dimensions. It omits the meaning of `mode` and `response_format`, which are the remaining gaps for a caller.

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 only 13%, so the description must compensate, and it largely does: it explains the semantics and defaults of `max_age_sec` and `min_drop_pct`, enumerates the market values, and describes the period and sport filters. It leaves `limit`, `mode` (live vs prematch) and `response_format` unaddressed, so it is not fully compensating.

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?

Names a specific signal ('prices that dropped sharply against their own recent history — the 'steam' signal') rather than restating the tool name. An agent can distinguish it from get_event_odds and get_prematch_lines without opening any schema.

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?

Gives concrete tuning guidance — defaults of last 10 minutes at 5%+, and explicitly how to broaden results via `max_age_sec` or `min_drop_pct`. It stops short of naming a sibling tool or stating when a different tool is the better choice.

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