ZeroGEX — SPX/SPY/QQQ/NDX dealer positioning

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

Annotations already mark it read-only, idempotent, and non-destructive, so the bar is lower; the description adds critical behavior: up to 15-minute delay, response states its own age, quote the age and never use live, and null levels mean unavailable rather than zero. No contradiction with 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?

Every sentence earns its place: purpose, use cases, data freshness, exclusions, and null-handling semantics. It is front-loaded with the core purpose and efficiently packs essential caveats without redundancy.

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?

For a single-parameter tool with no output schema, the description covers the full set of returned levels, the delay and age behavior, the non-price-feed/forecast nature, and how to interpret nulls. An agent has enough to call it correctly and interpret results.

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?

There is only one parameter with 100% schema coverage, including an enum and a description of futures projection. The description adds general context ('one underlying') but does not add meaningful parameter-level detail beyond the schema, so the baseline 3 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?

The description clearly identifies what the tool provides: modeled dealer-positioning levels (gamma flip, call wall, put wall, max pain, pin strike, net dealer gamma) for one underlying. The phrase 'for one underlying' distinguishes it from the market-wide sibling tool.

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?

It explicitly gives example queries such as 'where is the gamma flip' and 'is SPX in positive gamma', and states not to use it as a live price feed, forecast, or trade recommendation. It does not explicitly name the sibling alternative, but the 'one underlying' scope and 'never call live' instruction provide strong usage context.

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

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is covered. The description adds useful behavioral context: it returns delayed data (15-minute), is free, and omits certain details (walls, max pain, pin strike). It doesn't describe the exact output format, but with no output schema and a simple summary tool, the description provides adequate transparency.

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 compact and front-loaded: the first sentence states the core purpose and scope, the second gives usage examples, and the third provides the sibling routing rule. Every sentence earns its place with no redundancy.

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?

For a zero-parameter, read-only, idempotent tool with a single sibling, the description covers everything an agent needs: what it returns, when to use it, when not to use it, and the data caveats. The lack of an output schema is acceptable because the description names the fields (spot, modeled regime, gamma flip) and the tool is a simple summary.

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?

The tool has zero parameters, so the schema is trivially complete. The description explains what the tool returns without needing to document any parameters. Baseline 4 for zero-param tools is appropriate, and the description adds value by clarifying the scope of the response.

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 returns a one-line dealer-positioning summary for all six covered underlyings, listing the specific symbols and the data included (spot, modeled regime, gamma flip). It distinguishes itself from get_gamma_levels by explicitly noting it omits walls, max pain, and pin strike.

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 description gives explicit when-to-use guidance: broad openers like 'what does dealer positioning look like today' or 'which indices are in negative gamma'. It also names the alternative (get_gamma_levels) and the condition for choosing it (single-symbol questions), making the routing decision unambiguous.

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