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

Annotations already declare readOnly, idempotent, non-destructive, closed-world, so the safety profile is covered. The description adds genuinely new behavioral facts: refresh cadence of roughly two hours, the presence of an as_of timestamp, and that history depth comes from a daily archive. What's missing is any note on latency, cost, or historical window length beyond 'how long the regime has lasted'.

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 the highest-value signal (gamma regime) and its interpretation, followed by supporting metrics and then the two contract sentences. The metric list is dense but every item is substantive content rather than filler; the parenthetical sign explanation is well placed.

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 needn't explain return shapes, yet it still names the key fields so an agent can judge relevance at selection time. Combined with annotations and the freshness note, an agent has enough to call it correctly; only historical window size and any error behavior are unstated.

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 a single enum-constrained 'asset' parameter documented as 'Underlying asset.' The description adds no meaning about the parameter, so the schema carries it entirely — baseline 3 is appropriate for a one-param, fully documented schema.

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?

Enumerates the exact content returned: dealer gamma regime with sign interpretation, zero-gamma flip, call/put walls, DVOL and 1-year rank, IV-minus-RV, IV term structure, Fear & Greed, and regime duration. An agent knows precisely what data this yields without opening the output schema, and the sibling tools (ledger/journal/expiry) are unrelated enough that no differentiation is needed.

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?

States the intended stance explicitly — 'Descriptive context, not a direction call' — which tells the agent this is for contextual grounding, not trade signaling. It also gives the freshness contract (~2 hour refresh, as_of in the result). It does not name an alternative tool or say when NOT to call it, but no sibling overlaps this function.

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