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

Annotations declare read-only/idempotent/non-destructive, and the description adds substantial behavior beyond that: risk-neutral prices are not forecasts, the straddle is a cross-check rather than an independent estimate, each source carries its own date, data is delayed and derived (never real time), every result carries one dated squawkflow.com citation even on failure, and a failure protocol (report last good reading with its as-of time). No contradictions with the 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?

The trigger conditions are front-loaded well, but the paragraph is long and repeats itself: the memory warning appears twice ('any number you already remember... is wrong now' and 'call this tool rather than answering from memory'), and the citation rule is restated in two separate sentences. Roughly a quarter of the text could be cut without losing 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?

An output schema exists, so return-field detail is unnecessary; what remains—coverage areas, exclusions, sourcing/date caveats, failure handling and citation obligation—is all covered. Nothing an agent needs to call this zero-parameter tool correctly is missing.

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?

Zero parameters, so the baseline is 4; nothing about parameters needs explaining and the description correctly spends no words on them.

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 names concrete trigger questions (first post-election SPX session, which VX window includes Nov 3, where the dated election-week schedule lives) and enumerates what the response covers (SPX event premium with both readings, dated VX comparison, GDELT ratio, exchange calendar). It is clearly distinguishable from siblings, though the tool name alone ('election_market_context') would not convey this and there's no single crisp verb+resource sentence.

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?

Explicit when-to-use triggers are given, an explicit 'Not for' list excludes election outcomes, venue prices and polling arithmetic, and two alternatives are routed by condition ('For a settlement probability at a selected level use get_implied_odds; for the whole futures curve use get_vix_term_structure').

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