{
  "data": {
    "tool": {
      "category": "",
      "endpoint": "https://equation.io/mcp",
      "jsonUrl": "https://www.anchorterminal.com/api/v1/tools/equation.json",
      "kind": "mcp",
      "listed": "indexed",
      "liveUrl": "https://www.anchorterminal.com/api/v1/live/equation.json",
      "markdownUrl": "https://www.anchorterminal.com/tools/equation.md",
      "mcpTools": {
        "check": {
          "checker": "anchor-check/1.0",
          "totalTokens": 1559,
          "counts": {
            "error": 0,
            "note": 0,
            "warn": 0
          },
          "findings": []
        },
        "checkedAt": "2026-10-04T22:25:18Z",
        "count": 3,
        "note": "answered without the initialize handshake",
        "schemaTokens": 1559,
        "status": "ok",
        "tools": [
          {
            "name": "encode_graph_url",
            "title": "Create a graph link",
            "description": "Build an equation.io graph link, validating every row with the app's parser. Pass the COMPLETE graph in \"equations\": a flat array of strings, one equation or definition per string, in display order — when editing an existing graph (see decode_graph_url), include unchanged rows too.\n\nRows can be: equations and inequalities in x,y (curves, regions; z makes it 3D), bare expressions in x, y (scalar fields — a curve is written y = f(x); complex plots via w), points (rows report \"draggable\"), parametric tuples in u,v — and definitions: \"a = 2\" (a draggable slider), \"f(x) = x^3 - a x\", coordinate fields like \"r = sqrt(x^2+y^2)\" for polar. t animates. Also derivatives d/dx, integrals int[a..b] f dx, sums sum[n=1..N], domain()/conformal()/iter() for complex plots, rgb()/hsl()/oklch() color fields, y' = … slope fields, random variables \"X ~ Normal(m, s)\"/\"P(0\u003cX\u003c2)\"/\"E(X^2)\", and \"view(x = -5..5, y = -2..2)\"/\"camera(theta, phi)\" framing rows. That is a menu, not the syntax: before your first non-trivial graph, read the \"syntax\" MCP resource (also at https://equation.io/llms.txt).\n\nThe result returns text and structured data only. \"rows\" gives each equation's validation result: status \"ok\" with its kind, or \"error\" with the parser message. The link is usable only once every row is \"ok\". Give users the share_url (it unfurls to a preview card in chat apps); url is the equivalent #-fragment form. \"preview\" and \"preview_omits\" describe the share link's simplified static preview (t = 0, 3D as wireframes), which draws less than the interactive app. No image is attached to the tool response.",
            "inputSchema": {
              "additionalProperties": false,
              "properties": {
                "equations": {
                  "description": "Every equation in the graph, in display order. One equation or definition per string — do not join rows with \";\" (inside quoted text a \";\" is data, and kept).",
                  "items": {
                    "type": "string"
                  },
                  "type": "array"
                }
              },
              "required": [
                "equations"
              ],
              "type": "object"
            },
            "outputSchema": {
              "additionalProperties": false,
              "properties": {
                "preview": {
                  "description": "Static preview availability and limitations.",
                  "type": "string"
                },
                "preview_omits": {
                  "items": {
                    "additionalProperties": false,
                    "properties": {
                      "row": {
                        "type": "string"
                      },
                      "why": {
                        "type": "string"
                      }
                    },
                    "required": [
                      "row",
                      "why"
                    ],
                    "type": "object"
                  },
                  "type": "array"
                },
                "rows": {
                  "items": {
                    "anyOf": [
                      {
                        "additionalProperties": false,
                        "properties": {
                          "animated": {
                            "type": "boolean"
                          },
                          "draggable": {
                            "type": "boolean"
                          },
                          "kind": {
                            "type": "string"
                          },
                          "note": {
                            "type": "string"
                          },
                          "status": {
                            "enum": [
                              "ok"
                            ],
                            "type": "string"
                          },
                          "text": {
                            "type": "string"
                          },
                          "value": {
                            "type": "string"
                          }
                        },
                        "required": [
                          "text",
                          "status",
                          "kind"
                        ],
                        "type": "object"
                      },
                      {
                        "additionalProperties": false,
                        "properties": {
                          "error": {
                            "type": "string"
                          },
                          "status": {
                            "enum": [
                              "error"
                            ],
                            "type": "string"
                          },
                          "text": {
                            "type": "string"
                          }
                        },
                        "required": [
                          "text",
                          "status",
                          "error"
                        ],
                        "type": "object"
                      }
                    ]
                  },
                  "type": "array"
                },
                "share_url": {
                  "description": "Shareable /g/ graph URL.",
                  "type": "string"
                },
                "url": {
                  "description": "Graph URL using a #-fragment.",
                  "type": "string"
                },
                "valid": {
                  "type": "boolean"
                }
              },
              "required": [
                "valid",
                "url",
                "share_url",
                "preview",
                "rows"
              ],
              "type": "object"
            },
            "annotations": {
              "destructiveHint": false,
              "idempotentHint": true,
              "openWorldHint": false,
              "readOnlyHint": true,
              "title": "Create a graph link"
            }
          },
          {
            "name": "decode_graph_url",
            "title": "Read a graph link",
            "description": "Decode an equation.io link (either the #-fragment form or the /g/ share form) into its list of equation rows, so you can edit them and build a new link with encode_graph_url. The rows use the equation.io syntax documented in the \"syntax\" MCP resource (also at https://equation.io/llms.txt).",
            "inputSchema": {
              "properties": {
                "url": {
                  "description": "An equation.io graph URL.",
                  "type": "string"
                }
              },
              "required": [
                "url"
              ],
              "type": "object"
            },
            "outputSchema": {
              "additionalProperties": false,
              "properties": {
                "equations": {
                  "items": {
                    "type": "string"
                  },
                  "type": "array"
                }
              },
              "required": [
                "equations"
              ],
              "type": "object"
            },
            "annotations": {
              "destructiveHint": false,
              "idempotentHint": true,
              "openWorldHint": false,
              "readOnlyHint": true,
              "title": "Read a graph link"
            }
          },
          {
            "name": "show_graph",
            "title": "Show an interactive graph",
            "description": "Display an interactive equation.io graph inside the conversation, with editable equations, sliders, pan/zoom, and 3D rotation. Use when the user asks to see or explore a graph. Pass the COMPLETE graph as \"equations\", one equation or definition per string, preserving unchanged rows when editing. For a slider use \"a = 2\" then \"y = a sin(x)\". For advanced syntax read the \"syntax\" resource (https://equation.io/llms.txt). Returns per-row validation and share links; a row with status \"error\" is not drawn until its text is corrected and the graph resubmitted. Use encode_graph_url for validation or link-only requests (including share-link preview notes). In clients without UI support, provide share_url.",
            "inputSchema": {
              "additionalProperties": false,
              "properties": {
                "equations": {
                  "description": "Every equation in the graph, in display order. One equation or definition per string — do not join rows with \";\" (inside quoted text a \";\" is data, and kept).",
                  "items": {
                    "type": "string"
                  },
                  "type": "array"
                }
              },
              "required": [
                "equations"
              ],
              "type": "object"
            },
            "outputSchema": {
              "additionalProperties": false,
              "properties": {
                "rows": {
                  "items": {
                    "anyOf": [
                      {
                        "additionalProperties": false,
                        "properties": {
                          "animated": {
                            "type": "boolean"
                          },
                          "draggable": {
                            "type": "boolean"
                          },
                          "kind": {
                            "type": "string"
                          },
                          "note": {
                            "type": "string"
                          },
                          "status": {
                            "enum": [
                              "ok"
                            ],
                            "type": "string"
                          },
                          "text": {
                            "type": "string"
                          },
                          "value": {
                            "type": "string"
                          }
                        },
                        "required": [
                          "text",
                          "status",
                          "kind"
                        ],
                        "type": "object"
                      },
                      {
                        "additionalProperties": false,
                        "properties": {
                          "error": {
                            "type": "string"
                          },
                          "status": {
                            "enum": [
                              "error"
                            ],
                            "type": "string"
                          },
                          "text": {
                            "type": "string"
                          }
                        },
                        "required": [
                          "text",
                          "status",
                          "error"
                        ],
                        "type": "object"
                      }
                    ]
                  },
                  "type": "array"
                },
                "share_url": {
                  "description": "Shareable /g/ graph URL.",
                  "type": "string"
                },
                "url": {
                  "description": "Graph URL using a #-fragment.",
                  "type": "string"
                },
                "valid": {
                  "type": "boolean"
                }
              },
              "required": [
                "valid",
                "url",
                "share_url",
                "rows"
              ],
              "type": "object"
            },
            "annotations": {
              "destructiveHint": false,
              "idempotentHint": true,
              "openWorldHint": false,
              "readOnlyHint": true,
              "title": "Show an interactive graph"
            }
          }
        ]
      },
      "name": "Equation.io",
      "note": "Indexed from the official MCP registry: facts and our own checks, not reviewed, so no score, grade or rank.",
      "packages": null,
      "pageJsonUrl": "https://www.anchorterminal.com/tools/equation.json",
      "popularity": {
        "githubStars": 406
      },
      "registryName": "io.equation/equation",
      "remotes": [
        {
          "type": "streamable-http",
          "url": "https://equation.io/mcp"
        }
      ],
      "repository": "https://github.com/aantthony/equation.io",
      "reviewed": false,
      "slug": "equation",
      "source": "the official MCP registry",
      "sourceUrl": "https://registry.modelcontextprotocol.io/v0.1/servers?search=io.equation/equation",
      "summary": "Create interactive 2D and 3D graphs with validated equations, shareable links, and PNG previews.",
      "updatedAt": "2026-10-02T10:56:21Z",
      "url": "https://www.anchorterminal.com/tools/equation",
      "vendor": "equation.io",
      "vendorUrl": "https://equation.io",
      "version": "1.0.1",
      "websiteUrl": "https://equation.io",
      "where": "hosted",
      "why": [
        "vendor",
        "popular"
      ]
    }
  },
  "kind": "anchor.page",
  "links": {
    "api": "https://www.anchorterminal.com/api/v1/index.json",
    "html": "https://www.anchorterminal.com/tools/equation",
    "json": "https://www.anchorterminal.com/tools/equation.json",
    "llms": "https://www.anchorterminal.com/llms.txt",
    "markdown": "https://www.anchorterminal.com/tools/equation.md",
    "slim": "https://www.anchorterminal.com/tools/equation.min.md"
  },
  "markdown": "# Equation.io\n\n\u003e Indexed, not reviewed: facts from the official MCP registry and our own checks. No score, grade or rank, and not in the rankings until the panel reviews it. How the index works: https://www.anchorterminal.com/indexed/\n\n- Kind: MCP server, by equation.io (https://equation.io)\n- Listed because: It's published in the registry under equation.io, a namespace the registry only gives to whoever proves they control that domain. It's in real use: 406 GitHub stars.\n- What the official MCP registry says: Create interactive 2D and 3D graphs with validated equations, shareable links, and PNG previews.\n\n## Facts\n\n- MCP registry: `io.equation/equation` 1.0.1\n- Endpoint: https://equation.io/mcp (streamable HTTP)\n- Source: https://github.com/aantthony/equation.io\n- Website: https://equation.io\n- GitHub stars: 406\n- Registry entry updated: 2026-10-02\n\n## Tools\n\n- Tools it lists (3, about 1,559 tokens of context, `tools/list` without credentials, checked 2026-10-04 22:25 UTC):\n  - `encode_graph_url` (read-only): Build an equation.io graph link, validating every row with the app's parser. Pass the COMPLETE graph in \"equations\": a flat array of strings, one equation or…\n  - `decode_graph_url` (read-only): Decode an equation.io link (either the #-fragment form or the /g/ share form) into its list of equation rows, so you can edit them and build a new link with…\n  - `show_graph` (read-only): Display an interactive equation.io graph inside the conversation, with editable equations, sliders, pan/zoom, and 3D rotation. Use when the user asks to see or…\n- How its tools read to an agent (0 errors, 0 warnings, 0 notes, about 1,559 tokens; rules at https://www.anchorterminal.com/check.md; not part of the score):\n\n- JSON: https://www.anchorterminal.com/api/v1/tools/equation.json\n- Being indexed says nothing about quality, and nobody can pay for it. Ask for a review: https://www.anchorterminal.com/builders/#claiming\n",
  "meta": {
    "attribution": "Anchor Terminal (https://www.anchorterminal.com)",
    "docs": "https://www.anchorterminal.com/docs/",
    "generatedAt": "2026-10-05",
    "license": "CC-BY-4.0",
    "method": "https://www.anchorterminal.com/benchmark/",
    "methodology": "0.3",
    "openapi": "https://www.anchorterminal.com/openapi.json",
    "preview": false,
    "run": "2026-10-01",
    "runLabel": "October 2026 research run"
  },
  "page": {
    "breadcrumbs": [
      {
        "name": "Home",
        "url": "https://www.anchorterminal.com/"
      },
      {
        "name": "Terminal",
        "url": "https://www.anchorterminal.com/tools/"
      },
      {
        "name": "Indexed",
        "url": "https://www.anchorterminal.com/indexed/"
      },
      {
        "name": "Equation.io",
        "url": ""
      }
    ],
    "description": "Equation.io, an MCP server by equation.io, listed from the official MCP registry. Indexed, not reviewed: facts and our own checks, no score or ranking. Create interactive 2D and 3D graphs with validated equations, shareable links, and PNG previews.",
    "facts": [
      "not reviewed",
      "not ranked",
      "facts only"
    ],
    "h1": "Equation.io",
    "image": "https://www.anchorterminal.com/assets/og/indexed.png",
    "path": "/tools/equation",
    "published": "",
    "section": "indexed",
    "title": "Equation.io: MCP server, indexed from the official MCP registry",
    "toc": null,
    "updated": "2026-10-05",
    "url": "https://www.anchorterminal.com/tools/equation"
  },
  "tokens": {
    "markdown": 650,
    "slim": 580
  },
  "version": 1
}