{ "openapi": "3.1.1", "info": { "title": "Gas Fee Intelligence Explorer API", "version": "1.0.0", "summary": "Live gas on 7 EVM chains: base fee, tips, trend and the USD cost of transfers and swaps.", "description": "Every endpoint performs the same calculation as the human page and returns inputs, result, units, assumptions, sources, warnings and computedAt. MCP endpoint: /mcp." }, "servers": [ { "url": "https://gasfeeintelligenceexplorer.usefulweb.site" } ], "paths": { "/api/v1/calculate": { "post": { "operationId": "calculate", "summary": "Live gas on 7 EVM chains: base fee, tips, trend and the USD cost of transfers and swaps.", "description": "Pulls eth_feeHistory (last 100 blocks, 10th/50th/90th percentile tips) and eth_gasPrice from Ethereum, Base, Arbitrum, OP Mainnet, Polygon, Avalanche and BNB Chain, prices the native tokens via DefiLlama and shows what a native transfer, ERC-20 transfer and swap cost on each chain — ranked cheapest first, with OP Stack L1 data fees as an upper bound.\n\nMethodology:\n- eth_feeHistory(blockCount, \"latest\", [10, 50, 90]) per chain: base fee per block (the last entry is the next block's base fee) and the 10th/50th/90th percentile priority fee of each block; the tool takes the median of each percentile across blocks.\n- Price tiers = next base fee + median p10 (slow) / p50 (standard) / p90 (fast) tip. Chains without a base fee use eth_gasPrice. Trend compares the average base fee of the newest fifth of blocks with the oldest fifth (±15 %).\n- Operation costs use typical gas amounts — native transfer 21,000 (exact), ERC-20 transfer ≈ 65,000, DEX swap ≈ 150,000 (estimates; real usage varies by contract and state) — times the standard tier.\n- USD: native token prices from the DefiLlama coins API (coingecko:ethereum, polygon-ecosystem-token, avalanche-2, binancecoin).\n- L2 data fees: on Base and OP Mainnet the OP Stack GasPriceOracle (0x4200…000F) getL1FeeUpperBound(size) is added as an upper bound using approximate transaction sizes (50 / 120 / 350 bytes unsigned). Arbitrum's L1 component is not included (it is folded into gas used at execution time and needs a per-transaction estimate).", "tags": [ "web3" ], "x-mcp-tool": "gas_fee_intelligence_explorer", "requestBody": { "required": true, "content": { "application/json": { "schema": { "$ref": "#/components/schemas/GasFeeIntelligenceExplorerInput" }, "examples": { "example1": { "summary": "Ethereum vs Base vs Polygon from pasted data (offline)", "value": { "mode": "pasted", "pasted": "{\"prices\":{\"ETH\":2400,\"POL\":0.25,\"BNB\":600},\"chains\":{\"ethereum\":{\"gasPrice\":\"0x77359400\",\"feeHistory\":{\"oldestBlock\":\"0x1406f40\",\"baseFeePerGas\":[\"0x6fc23ac00\",\"0x77359400\",\"0x6fc23ac00\",\"0x684ee1800\",\"0x6fc23ac00\",\"0x74a3df240\"],\"gasUsedRatio\":[0.62,0.41,0.38,0.55,0.6],\"reward\":[[\"0x3b9aca0\",\"0x5f5e100\",\"0x77359400\"],[\"0x2faf080\",\"0x5f5e100\",\"0x3b9aca00\"],[\"0x0\",\"0x3b9aca0\",\"0x77359400\"],[\"0x2faf080\",\"0x5f5e100\",\"0x3b9aca00\"],[\"0x3b9aca0\",\"0x77359400\",\"0xb2d05e00\"]]}},\"base\":{\"gasPrice\":\"0x1312d00\",\"feeHistory\":{\"oldestBlock\":\"0x16e3600\",\"baseFeePerGas\":[\"0xf4240\",\"0xf4240\",\"0x10c8e0\",\"0xf4240\",\"0xe4e1c\",\"0xf4240\"],\"gasUsedRatio\":[0.31,0.29,0.35,0.3,0.28],\"reward\":[[\"0x0\",\"0xf4240\",\"0x989680\"],[\"0x0\",\"0xf4240\",\"0x989680\"],[\"0x0\",\"0xf4240\",\"0x1312d00\"],[\"0x0\",\"0xf4240\",\"0x989680\"],[\"0x0\",\"0x7a120\",\"0x989680\"]]},\"l1FeeUpperBoundWei\":{\"eth-transfer\":\"0x9184e72a00\",\"erc20-transfer\":\"0xdf8475800\",\"swap\":\"0x2540be400\"}},\"polygon\":{\"gasPrice\":\"0x6fc23ac000\",\"feeHistory\":{\"oldestBlock\":\"0x4c4b400\",\"baseFeePerGas\":[\"0x5d21dba000\",\"0x5d21dba000\",\"0x5d21dba000\",\"0x5d21dba000\",\"0x5d21dba000\",\"0x5d21dba000\"],\"gasUsedRatio\":[0.5,0.48,0.52,0.51,0.5],\"reward\":[[\"0x6fc23ac00\",\"0x6fc23ac00\",\"0x1176592e00\"],[\"0x6fc23ac00\",\"0x6fc23ac00\",\"0x1176592e00\"],[\"0x6fc23ac00\",\"0x6fc23ac00\",\"0x1176592e00\"],[\"0x6fc23ac00\",\"0x6fc23ac00\",\"0x1176592e00\"],[\"0x6fc23ac00\",\"0x6fc23ac00\",\"0x1176592e00\"]]}}}}" } } } } } }, "responses": { "200": { "description": "Calculation result envelope.", "content": { "application/json": { "schema": { "$ref": "#/components/schemas/GasFeeIntelligenceExplorerResult" } } } }, "400": { "description": "Malformed JSON body.", "content": { "application/problem+json": { "schema": { "$ref": "#/components/schemas/Problem" } } } }, "422": { "description": "Invalid input (see errors[]).", "content": { "application/problem+json": { "schema": { "$ref": "#/components/schemas/Problem" } } } }, "429": { "description": "Rate limit exceeded (see Retry-After).", "content": { "application/problem+json": { "schema": { "$ref": "#/components/schemas/Problem" } } } } } } }, "/api/v1/tool": { "get": { "operationId": "getToolDefinition", "summary": "Inputs, output schema and examples for this tool", "responses": { "200": { "description": "Tool definition.", "content": { "application/json": { "schema": { "type": "object" } } } } } } } }, "components": { "schemas": { "Problem": { "type": "object", "description": "RFC 9457 problem details. 422 responses include per-field `errors`.", "required": [ "type", "title", "status", "detail" ], "properties": { "type": { "type": "string" }, "title": { "type": "string" }, "status": { "type": "integer" }, "detail": { "type": "string" }, "code": { "type": "string" }, "errors": { "type": "array", "items": { "type": "object", "required": [ "field", "message" ], "properties": { "field": { "type": "string" }, "message": { "type": "string" } } } } } }, "GasFeeIntelligenceExplorerInput": { "type": "object", "additionalProperties": false, "properties": { "mode": { "title": "Data source", "type": "string", "enum": [ "live", "pasted" ], "default": "live" }, "chains": { "title": "Chains", "type": "array", "items": { "type": "string", "enum": [ "ethereum", "base", "arbitrum", "optimism", "polygon", "avalanche", "bsc" ] }, "default": [ "ethereum", "base", "arbitrum", "optimism", "polygon", "avalanche", "bsc" ] }, "blocks": { "title": "Blocks of fee history", "type": "integer", "minimum": 10, "maximum": 100, "default": 100 }, "pasted": { "title": "Pasted JSON", "description": "{\"prices\":{\"ETH\":2400},\"chains\":{\"ethereum\":{\"feeHistory\":{…eth_feeHistory result…},\"gasPrice\":\"0x…\",\"l1FeeUpperBoundWei\":{\"erc20-transfer\":\"0x…\"}}}}", "type": "string", "maxLength": 1000000 } }, "required": [] }, "GasFeeIntelligenceExplorerResult": { "type": "object", "additionalProperties": false, "required": [ "schemaVersion", "tool", "computedAt", "inputs", "summary", "result", "units", "assumptions", "sources", "warnings", "presentation", "links" ], "properties": { "schemaVersion": { "type": "string", "const": "1.0" }, "tool": { "type": "object", "additionalProperties": false, "required": [ "id", "name", "version" ], "properties": { "id": { "type": "string" }, "name": { "type": "string" }, "version": { "type": "string" } } }, "computedAt": { "type": "string", "format": "date-time" }, "inputs": { "type": "object", "description": "Normalised inputs actually used, including applied defaults." }, "summary": { "type": "string" }, "result": { "type": "object", "additionalProperties": false, "required": [ "mode", "chains", "ranking", "operations" ], "properties": { "mode": { "type": "string" }, "chains": { "type": "array", "items": { "type": "object", "additionalProperties": false, "required": [ "chain", "name", "native", "priceUsd", "oldestBlock", "newestBlock", "blocks", "baseFeeGwei", "priorityGwei", "gasPriceGwei", "avgGasUsedRatio", "trend", "tiersGwei", "operations", "l1DataFee", "error" ], "properties": { "chain": { "type": "string" }, "name": { "type": "string" }, "native": { "type": "string" }, "priceUsd": { "type": [ "number", "null" ] }, "oldestBlock": { "type": [ "integer", "null" ] }, "newestBlock": { "type": [ "integer", "null" ] }, "blocks": { "type": [ "integer", "null" ] }, "baseFeeGwei": { "type": [ "object", "null" ], "additionalProperties": false, "required": [ "next", "min", "avg", "max" ], "properties": { "next": { "type": "number" }, "min": { "type": "number" }, "avg": { "type": "number" }, "max": { "type": "number" } } }, "priorityGwei": { "type": [ "object", "null" ], "additionalProperties": false, "required": [ "p10", "p50", "p90" ], "properties": { "p10": { "type": "number" }, "p50": { "type": "number" }, "p90": { "type": "number" } } }, "gasPriceGwei": { "type": [ "number", "null" ] }, "avgGasUsedRatio": { "type": [ "number", "null" ] }, "trend": { "type": [ "string", "null" ] }, "tiersGwei": { "type": [ "object", "null" ], "additionalProperties": false, "required": [ "slow", "standard", "fast" ], "properties": { "slow": { "type": "number" }, "standard": { "type": "number" }, "fast": { "type": "number" } } }, "operations": { "type": "array", "items": { "type": "object", "additionalProperties": false, "required": [ "operation", "gas", "executionNative", "l1DataFeeNative", "totalNative", "totalUsd" ], "properties": { "operation": { "type": "string" }, "gas": { "type": "integer" }, "executionNative": { "type": "number" }, "l1DataFeeNative": { "type": [ "number", "null" ] }, "totalNative": { "type": "number" }, "totalUsd": { "type": [ "number", "null" ] } } } }, "l1DataFee": { "type": "string", "enum": [ "included-upper-bound", "not-included", "not-applicable" ] }, "error": { "type": [ "string", "null" ] } } } }, "ranking": { "type": "array", "items": { "type": "object", "additionalProperties": false, "required": [ "rank", "chain", "erc20TransferUsd", "erc20TransferNative" ], "properties": { "rank": { "type": "integer" }, "chain": { "type": "string" }, "erc20TransferUsd": { "type": [ "number", "null" ] }, "erc20TransferNative": { "type": "number" } } } }, "operations": { "type": "array", "items": { "type": "object", "additionalProperties": false, "required": [ "id", "label", "gas" ], "properties": { "id": { "type": "string" }, "label": { "type": "string" }, "gas": { "type": "integer" } } } } } }, "units": { "type": "object", "additionalProperties": { "type": "string" } }, "assumptions": { "type": "array", "items": { "type": "string" } }, "sources": { "type": "array", "items": { "type": "object", "additionalProperties": false, "required": [ "title" ], "properties": { "title": { "type": "string" }, "url": { "type": "string" }, "publisher": { "type": "string" }, "retrievedAt": { "type": "string" }, "note": { "type": "string" } } } }, "warnings": { "type": "array", "items": { "type": "string" } }, "presentation": { "type": "array", "items": { "type": "object" }, "description": "Display blocks used by the human page (same data)." }, "links": { "type": "object", "additionalProperties": false, "required": [ "human", "api", "openapi", "methodology" ], "properties": { "human": { "type": "string", "format": "uri" }, "api": { "type": "string", "format": "uri" }, "openapi": { "type": "string", "format": "uri" }, "methodology": { "type": "string", "format": "uri" } } } } } } } }