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

Annotations already declare read-only, idempotent, and non-destructive. The description adds value by explaining the behavior of each kind (e.g., 'anomalies' includes volume_spike/phantom_tick with severity bands), the default kind, and what happens for empty/unknown kind. It also explicitly states 'Market DATA, NOT advice', disclosing the nature of the output.

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 a single efficient paragraph, front-loading the main purpose and then detailing kinds. Every sentence adds value. Could be slightly improved by using bullet points for the three kinds, but current structure is clear and not verbose.

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 an output schema present, the description does not need to detail return values. It covers all necessary context: what each kind returns, endpoints invoked implicitly, edge cases (unknown/empty kind), and usage intent (market context before drilling). The combo of annotations, schema, and description leaves no gaps.

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% with existing descriptions. The description goes beyond the schema by explaining the default behavior for kind (movers), the clamping and effective ranges for limit, and the case/space-insensitivity and scope (anomalies only) for symbol. This provides practical context for parameter usage.

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 is for whole-market reads grouped by kind, listing three distinct modes: movers, overview, anomalies. It specifies the action (get market board) and differentiates from sibling tools like get_candles or get_signals by emphasizing it's top-level context before drilling into specific symbols.

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?

Explicitly says 'find what's MOVING before drilling into one symbol', providing clear usage context. It notes when to use this tool (initial market context) and implies when not to (for detailed single-symbol analysis). Could be improved by listing alternative tools more directly.

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