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MCP endpoint: /mcp." }, "servers": [ { "url": "https://ohmforgeresistornetwork.usefulweb.app" } ], "paths": { "/api/v1/calculate": { "post": { "operationId": "calculate", "summary": "Series/parallel resistor networks: total resistance, power per part, best E-series combinations.", "description": "Two jobs in one: find the combination of up to three standard resistors (E6 to E192) that comes closest to a resistance you cannot buy, or evaluate a series/parallel expression such as 100 + (220 || 330) with the voltage, current and power of every resistor at a given voltage.\n\nMethodology:\n- Evaluate: series resistances add, parallel conductances add (1/R = Σ 1/Ri). The applied voltage is divided along series branches in proportion to their resistance and appears in full across each parallel branch; P = V² / R per resistor.\n- Find: one part = the nearest series value. Two parts: every series value a below (series) or above (parallel) the target is tried with the two series neighbours of the exact partner (T − a, or 1/(1/T − 1/a)). Three parts: every pair a ≤ b with the exact third value for a + b + c, a ∥ b ∥ c, (a + b) ∥ c and (a ∥ b) + c, again rounded down and up. Values span target/100 … target·100 (target/10 … target·10 for the first two parts of three-part E48 … E192 combinations).\n- Ranking: smallest |error|, then fewer parts. The best result for 1, 2 and 3 parts is listed separately so you can see what an extra resistor buys.\n\nNominal values only: the tolerance of each part (5 % for E24, 1 % for E96) usually exceeds the combination error, so measure or use tighter-tolerance parts where accuracy matters. Check the power rating of every resistor.", "tags": [ "apps" ], "x-mcp-tool": "ohmforge_resistor_network", "x-owner-app": "ohmforge", "requestBody": { "required": true, "content": { "application/json": { "schema": { "$ref": "#/components/schemas/OhmforgeResistorNetworkInput" }, "examples": { "example1": { "summary": "Make 1234 Ω from E12 parts", "value": { "mode": "find", "target": "1234", "series": "E12", "maxParts": "3" } }, "example2": { "summary": "12.5 Ω from E24 (two parts)", "value": { "mode": "find", "target": "12.5", "series": "E24", "maxParts": "2" } }, "example3": { "summary": "100 + (220 || 330) at 10 V", "value": { "mode": "evaluate", "expression": "100 + (220 || 330)", "voltage": 10 } } } } } }, "responses": { "200": { "description": "Calculation result envelope.", "content": { "application/json": { "schema": { "$ref": "#/components/schemas/OhmforgeResistorNetworkResult" } } } }, "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" } } } } } }, "OhmforgeResistorNetworkInput": { "type": "object", "additionalProperties": false, "properties": { "mode": { "title": "Task", "type": "string", "enum": [ "find", "evaluate" ], "default": "find" }, "target": { "title": "Target resistance", "description": "For \"find\": engineering notation, e.g. 1234, 2k15, 12.5.", "type": "string", "maxLength": 32, "default": "1234" }, "series": { "title": "Standard resistor series", "type": "string", "enum": [ "E6", "E12", "E24", "E48", "E96", "E192" ], "default": "E24" }, "maxParts": { "title": "Resistors at most", "type": "string", "enum": [ "1", "2", "3" ], "default": "3" }, "expression": { "title": "Network expression", "description": "For \"evaluate\": values joined with + (series) and || or // (parallel); parentheses group; || binds tighter than +.", "type": "string", "maxLength": 2000, "default": "100 + (220 || 330)" }, "voltage": { "title": "Voltage across the network", "description": "For \"evaluate\": used for the current and power of each resistor.", "type": "number", "minimum": 0, "maximum": 100000, "default": 10, "x-unit": "V" } }, "required": [] }, "OhmforgeResistorNetworkResult": { "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", "required": [ "mode" ], "additionalProperties": false, "properties": { "mode": { "type": "string" }, "target": { "type": "number" }, "series": { "type": "string" }, "combinations": { "type": "array", "items": { "type": "object", "additionalProperties": false, "properties": { "expression": { "type": "string" }, "shape": { "type": "string" }, "values": { "type": "array", "items": { "type": "number" } }, "ohms": { "type": "number" }, "errorPercent": { "type": "number" }, "parts": { "type": "integer" } } } }, "bestByParts": { "type": "array", "items": { "type": "object", "additionalProperties": false, "properties": { "parts": { "type": "integer" }, "expression": { "type": "string" }, "ohms": { "type": "number" }, "errorPercent": { "type": "number" } } } }, "expression": { "type": "string" }, "totalResistance": { "type": "number" }, "voltage": { "type": "number" }, "totalCurrent": { "type": "number" }, "totalPower": { "type": "number" }, "resistors": { "type": "array", "items": { "type": "object", "additionalProperties": false, "properties": { "name": { "type": "string" }, "ohms": { "type": "number" }, "voltage": { "type": "number" }, "current": { "type": "number" }, "power": { "type": "number" } } } } } }, "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" } } } } } } } }