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

Goes well beyond annotations: discloses that matching is whole-token over title/domain/url only, that article text is never read, that tags are computed by the service rather than reported by GDELT, and that each call costs $0.01 via x402 with the exact retry mechanism. This also reconciles readOnlyHint=false (it spends funds) which would otherwise look odd. Missing only result-cap/pagination behavior.

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 core identity, then matching semantics, payload shape, preflight guidance and payment mechanics in a logical order. Dense but nearly all functional; the HTTP-equivalent line is marginal extra weight.

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 partially compensates by naming returned fields (computed_tags {assets, topics}, crypto_native_source) plus taxonomy version. Pricing, preflight and payment flow are covered; response size/pagination remains unspecified.

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 60%, with asset/topic/lang already documented inline including example values. The description adds that asset/topic ids come from the crypto-v1 taxonomy and that filters work by headline token matching, but says nothing about `days` (default 7, max 31) or `limit` beyond what the schema states. Baseline 3 fits.

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 and scope: a crypto-vertical GDELT news feed with deterministic whole-token headline matching. It distinguishes itself from the generic gdelt_news_clusters/news_search siblings by naming the crypto taxonomy and computed_tags payload.

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?

Explicitly routes the agent to gdelt_news_crypto_preflight for a free coverage check before spending money, and gives the paid-call mechanics. It does not explicitly contrast with non-crypto siblings (news_search, gdelt_news_clusters), so the alternative-selection guidance is partial.

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