Current gas price and estimated simple-transfer cost for an EVM chain. Free preview route. Supports base, polygon, arbitrum, optimism, ethereum.
| Name | Required | Description | Default |
|---|---|---|---|
| chain | No | Which chain to query. Defaults to base. |
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description must disclose behavioral traits itself. It does reveal that the route is free and that the data is 'current', which is useful context, but it omits details like authentication needs, rate limits, and output units. Still, the key free-preview trait is disclosed.
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 a single front-loaded sentence with no redundancy. It puts the core purpose first, then the free-preview note, then the chain list, making it highly scannable.
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 tool with one optional parameter and no output schema, the description gives enough to select the chain and understand the high-level return values. It could clarify units of the gas price or transfer cost, but the tool is simple enough that an agent can call it correctly.
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 schema already fully documents the only parameter 'chain' with an enum and a default. The description's list of supported chains merely repeats the enum, adding no new meaning beyond what the schema provides.
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 states a specific resource ('Current gas price and estimated simple-transfer cost') and the supported chains, making the tool's intent unmistakable. It is clearly differentiated from sibling tools like x402_audit_merchant or x402_check_endpoint, which target different concerns.
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 'Free preview route' implies a lightweight, no-cost use case, and the chain list gives some context. However, it never explicitly says when to use this tool versus alternatives like x402_market_stats, and it offers no exclusions or when-not-to-use guidance.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
Add one secure layer between your agents and this server.
Each tool targets a distinct aspect of the x402 ecosystem: endpoint liveness, deep merchant audit, facilitator comparison, gas pricing, market analytics, and verified merchant listings. There is no real overlap between tools.
All tools share the x402_ prefix and snake_case, but only audit_merchant and check_endpoint follow a verb_noun pattern. The remaining tools are noun phrases like gas_price, market_stats, and verified_merchants, making the naming conventions mixed yet still readable.
Six tools is well-scoped for an ecosystem intelligence server. Each tool fills a distinct niche and none feel redundant or superfluous.
The tool set covers the entire discovery and research workflow for the x402 economy: checking endpoints, finding verified merchants, auditing merchant trustworthiness, choosing facilitators, estimating gas costs, and assessing market viability. No obvious dead ends or critical gaps.