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

Annotations already declare readOnly/openWorld/idempotent/non-destructive, so the safety profile is covered. The description goes beyond that with genuinely useful behavior: a 6h-prefetched cache, GDELT DOC 2.0 as source, 100+ languages, no key required, and a per-call x402 price of 0.03 USDC on Base. Cost and cache-freshness are exactly the kind of disclosure annotations cannot carry.

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?

One front-loaded block that states the output signals first, then source/cache, then price. Dense but every clause carries information; slightly compressed by em-dashes and bracketed pricing, but no wasted sentences.

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 usefully enumerates the returned signals (mention spike vs baseline, tone shift, escalation flag, headlines). The remaining gap is that the single input parameter's accepted fields are never explained, so an agent knows what it gets back but not fully how to shape the request.

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% and there is only one parameter, so the baseline is 3. However, the schema itself is a generic wrapper ('product parameters (JSON or text)') with only a query example, and the description adds no syntax or supported-field detail, so nothing compensates for that vagueness.

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 a specific resource and verb-like function: a geopolitical tension index computed from news-mention spikes vs a 7-day baseline, tone shift, escalation flag, and driving headlines. That is far more concrete than a tautology. It does not explicitly differentiate itself from siblings (e.g., polymarket_markets, synthora_search), but the domain is distinct enough that ambiguity is low.

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 early signal for Polymarket geopolitical markets (high variance, high spread)' implies when the tool is useful, but it never states when not to use it or which sibling to pick instead. Usage is inferable rather than explicit, landing at the minimum-viable level.

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