Requires a ChainHelix API key as bearer token, or 2 cents per call paid over Binance b402 in USDT, USDC, USD1 or U on BNB Smart Chain, or over x402 in USDC on the Base network. Near term option implied volatility for Bitcoin and Ethereum, now vs one week ago
| Name | Required | Description | Default |
|---|---|---|---|
No arguments | |||
| Name | Required | Description | Default |
|---|---|---|---|
| results | Yes |
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full behavioral disclosure burden. It explicitly states authentication requirements ('ChainHelix API key as bearer token') and payment alternatives (2 cents per call via Binance or x402), which are critical for an agent to invoke the tool successfully. However, it does not mention read-only status, rate limits, or return shape, but these are less critical given the output schema exists.
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 run-on first sentence about payment/auth details, burying the actual purpose in the second sentence. It is not front-loaded; the main verb (implied volatility) appears only after a lengthy prerequisite clause. The content is useful but poorly structured and could be split into two focused 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?
Given zero parameters, no annotations, and an existing output schema, the description covers the essential function and access requirements. However, it leaves ambiguities such as what 'near term' means (e.g., specific expiry durations) and how the temporal comparison is presented. The payment details are overemphasized relative to the functional description, but overall the tool is simple enough that this is minimally viable.
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 input schema is empty (0 parameters), so schema coverage is trivially 100%. The baseline for 0 parameters is 4. The description adds context about the data content (Bitcoin and Ethereum, near term, now vs one week ago), which helps the agent understand what the tool will return, even though there are no parameter details to clarify.
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 core purpose is clearly stated: 'Near term option implied volatility for Bitcoin and Ethereum, now vs one week ago.' This identifies a specific resource (implied volatility for BTC/ETH) and a temporal comparison, distinguishing it from siblings like 'prices' or 'congestion.' It lacks an explicit verb like 'provides' but the intent is unambiguous.
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 usage (when you need implied volatility data) but provides no explicit guidance on when to use this tool versus alternatives, nor any exclusions. The heavy focus on payment/authentication requirements does not help with selection criteria compared to other market data tools.
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.
Most tools have clearly distinct purposes, but some overlap exists among report tools (situation_report, deep_report, market_state) and spec tools (attest_spec, proof_spec). These could confuse an agent selecting the most appropriate endpoint.
Tool names use consistent snake_case and are descriptive, but follow mixed patterns: verb_noun for actions (buy_key, list_attestations) and bare nouns or noun phrases for data endpoints (prices, congestion, wall_map). This is readable but not fully uniform.
With 26 tools, the set is heavy and covers multiple domains (attestation, market data, key management, webhooks). It sits just above the borderline for comfort, but the breadth is justifiable given the server's multi-purpose nature.
The tool surface provides full lifecycle coverage for attestation (create, read, verify), key management (buy, claim, status), and webhooks (register, status, unregister), plus a wide range of market data endpoints. There are no obvious gaps or dead ends.