x402_api_onesource_io_api_chain_call_32[PAID inbound $0.0055 → then proxy $0.0055] Simulate a read-only Ethereum contract call via eth_call - no transaction sent Upstream: https://api.onesource.io/api/chain/call Method: POST
| Name | Required | Description | Default |
|---|---|---|---|
| body | No | Optional JSON body for non-GET requests | |
| query | No | Optional query string parameters for the upstream HTTP request |
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the burden of behavioral disclosure. It does disclose that the operation is read-only, sends no transaction, and includes cost and upstream URL/method details. However, it does not explain auth requirements, output/return behavior, error cases, or how the body/query are forwarded to eth_call.
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 brief and dense, conveying cost, purpose, upstream, and HTTP method in a single line with no wasted words. The pricing bracket is placed first, slightly delaying the core purpose, but the rest is well-organized.
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?
There is no output schema, annotations are absent, and the input schema is generic. The description does not tell an agent how to compose the eth_call request or interpret the response, which is a significant gap for a generic POST proxy among many similar endpoint tools.
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 description coverage is 100%, so the baseline is 3. The description adds no parameter-specific meaning: the schema only provides generic 'body' and 'query' objects, and the description does not explain how to structure the eth_call payload (e.g., contract address, calldata, block).
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 operation: simulate a read-only Ethereum contract call via eth_call, and explicitly notes no transaction is sent. This distinguishes it from sibling chain endpoints like tx_hash, estimate_gas, and balance endpoints by naming the exact RPC method and behavior.
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 description implies when to use the tool — for read-only contract simulation without sending a transaction — but it gives no explicit guidance on when not to use it or which alternative sibling tools to choose instead. With many similar chain_* tools, clearer routing would help.
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.
The core dispatcher tools are distinct, but the 84 auto-discovered wrappers contain dozens of near-identical news, weather, and translation endpoints. An agent cannot reliably tell many of these apart without reading provider-specific details, and misselection is likely.
Core tools use a readable verb_noun pattern, but most tools are machine-generated `x402_<domain>_<path>_<number>` names with opaque numeric suffixes. The two naming schemes are mixed, and the generated names are not intuitive.
95 tools is an extreme mismatch for a coherent MCP surface. The bulk are auto-registered third-party proxies that duplicate the same few categories, creating massive prompt bloat and selection overhead.
For an x402 dispatcher, the core lifecycle is well covered: discovery, search, quote, route-and-call, stats, paywall status, and cashflow/P&L. Minor gaps such as no deregistration or detailed per-transaction drill-down exist, but main workflows do not dead-end.