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

Annotations already declare readOnly/idempotent/openWorld, but the description adds substantial beyond them: free delayed data at least 15 minutes stale, the response self-reports its age and that age must be quoted, and null means 'unsupported by the modeled book' rather than zero. These are exactly the behavioral caveats an agent could otherwise get wrong.

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?

Front-loaded with what the tool returns, then usage triggers, then data-freshness caveat, then the null rule. Dense but every sentence carries load; nothing is redundant padding.

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, the description compensates by naming every returned level field and defining the null case explicitly. An agent has everything needed to interpret results and quote freshness correctly.

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% and the single enum parameter is already documented opaquely in the schema (ES/NQ projection caveat). The description adds no further param-level meaning, so the baseline of 3 for high schema coverage applies.

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?

States a specific verb+resource ('modeled options dealer-positioning levels for one underlying') and enumerates the exact levels returned (gamma flip, call wall, put wall, max pain, pin strike, net dealer gamma). An agent knows precisely what comes back. It does not explicitly contrast itself with sibling get_market_gamma_overview, so it falls short of full sibling differentiation.

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 triggering questions ('where is the gamma flip', 'where are the walls', 'is SPX in positive gamma') and clear when-not guidance (not a price feed, not a forecast, not a trade recommendation, never call live). Strong context, but it never names the sibling alternative or states the condition that would route an agent to get_market_gamma_overview.

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