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

Annotations already declare read-only, idempotent, open-world, non-destructive behavior, so the safety bar is met. The description adds genuinely useful operational context beyond that: the data source (GDELT DOC 2.0, 100+ languages, free, no key), a 6h-prefetched cache implying data freshness limits, and a per-call x402 cost of 0.03 USDC on Base. Rate limits and failure modes are not stated, keeping it below a 5.

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 tool's function and dense with information; the cost and source details earn their place. The redundant 'SYNTHORA gdelt-tension:' self-reference and branding prefix add slight noise, and the schema description repeats this text, but the description itself wastes little space.

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 one-parameter, read-only tool with no output schema, the description adequately covers what is returned (index values, spike ratio, tone shift, escalation flag, headlines) and the data provenance. Freshness is conveyed via the 6h cache note. It stops short of documenting response shape details or edge cases, but the essentials for correct invocation are present.

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?

With one parameter at 100% schema coverage, baseline is 3. The description adds only an implicit signal that the input is a topic/country string ('for any topic/country'), while the schema's own parameter text is just a truncated repeat of the description and does not explain expected input format. No syntax, examples, or matching rules are contributed.

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 resource (geopolitical tension index for any topic/country) with concrete outputs: 'news-mention spike vs 7d baseline, average tone shift, escalation flag and the headlines causing it.' It also positions itself against siblings by framing the use case relative to Polymarket geopolitical markets, so an agent can distinguish it from polymarket_markets or polymarket_trades.

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 phrase 'The early signal for Polymarket geopolitical markets (high variance, high spread)' implies when this is useful, but no explicit when-to-use vs when-not, no named alternatives, and no prerequisite conditions are given. Usage is inferrable from context rather than stated.

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