FreightUtils MCP Server

emissions_calculator

Read-onlyIdempotent

Estimate freight transport greenhouse-gas emissions (kgCO2e) for a shipment leg using mass, distance, and mode. Returns factor-based well-to-wheel or tank-to-wheel results per ISO 14083/GLEC.

Instructions

Estimate freight transport greenhouse-gas emissions (kgCO2e) for a shipment leg, per ISO 14083:2023 / GLEC Framework v3.2: emissions = mass x distance x a published emission-intensity factor (kgCO2e/tonne-km).

Provide mass + distance_km + mode (road | rail | sea | air | inland_waterway); optionally choose sub_mode, region/authority (uk = DEFRA, us = EPA, fr = ADEME) and basis (wtw default, or ttw). IMPORTANT: pass ACTUAL GROSS MASS, not chargeable/volumetric weight (a common air-freight mistake — see mass_basis in the result). Distance must be provided — this tool does NOT route, geocode, or compute distances.

Behavior: deterministic given the same factor edition; the fleet-average factor already includes average empty running (see empty_running) — do NOT add your own empty-return leg; sea and air are low-representativeness generic defaults (real emissions vary materially by vessel/aircraft, load factor and routing — see representativeness and the result summary). An unknown mode/sub_mode/region returns available:false with the covered options, never a fabricated factor. Rate-limited: a limit error carries reset_at, the UTC time the allowance resets.

Returns: well-to-wheel AND tank-to-wheel emissions where the factor has both, the exact factor used (value, authority, edition), the tonne-km activity and a per-result _source citing BOTH the ISO method and the specific published factor, all under result, plus confidence, _source and citation (the FreightUtils v1 response envelope).

Limitations: best-effort reference estimate from published factors (DEFRA / EPA / ADEME) — NOT a verified or audited carbon report.

Related: distinct from cbm_calculator / ldm_calculator / chargeable_weight_calculator (those size or bill a shipment; this one estimates its CO2e).

Input Schema

TableJSON Schema

Name	Required	Description
`mass`	Yes	Shipment mass, expressed in mass_unit. Example: 1000.
`mode`	Yes	Transport mode.
`basis`	No	Emissions basis: wtw = well-to-wheel incl. upstream (default), ttw = tank-to-wheel / operation only. When the factor publishes only the other basis the answer uses it and says so (basis_note, BASIS_SUBSTITUTED).
`region`	No	Factor source/region: uk = DEFRA, us = EPA, fr = ADEME. Default is per-mode.
`sub_mode`	No	Optional sub-mode / vehicle class (e.g. "articulated", "container ship", "long-haul"). Omit for the representative default.
`mass_unit`	No	Unit for mass. Default: kg.
`distance_km`	Yes	Transport distance in kilometres — you provide it; the tool does not route.

Output Schema

TableJSON Schema

Name	Required	Description	Default
`ok`	Yes
`result`	Yes
`_source`	Yes
`citation`	Yes
`validity`	No
`warnings`	No
`confidence`	Yes
`blocking_errors`	No
`envelope_version`	Yes
`normalized_input`	No

Schema Changelog

Changes observed during successful MCP inspections.

Changed1 schema field changedv2.22.3Oct 14, 2026

changedInput schema / properties / basis / description

Previous value: -"Emissions basis: wtw = well-to-wheel incl. upstream (default), ttw = tank-to-wheel / operation only."New value: +"Emissions basis: wtw = well-to-wheel incl. upstream (default), ttw = tank-to-wheel / operation only. When the factor publishes only the other basis the answer uses it and says so (basis_note, BASIS_SUBSTITUTED)."

Changed5 schema fields changedv2.17.2Aug 21, 2026
- addedOutput schema / properties / _source / properties / authority_current_edition
```
Added value: +{
+  "type": "string"
+}
```
- addedOutput schema / properties / _source / properties / checked_at
```
Added value: +{
+  "type": "string"
+}
```
- addedOutput schema / properties / _source / properties / dataset_edition
```
Added value: +{
+  "type": "string"
+}
```
- removedOutput schema / properties / envelope_version / const
```
Removed value: -"1"
```
- addedOutput schema / properties / envelope_version / enum
```
Added value: +[
+  "1",
+  "1.1"
+]
```

Changed40 schema fields changedv2.11.0Jul 10, 2026

changedInput schema / properties / basis / description

Previous value: -"Emissions basis: wtw = well-to-wheel incl. upstream (default), ttw = tank-to-wheel / operation only"New value: +"Emissions basis: wtw = well-to-wheel incl. upstream (default), ttw = tank-to-wheel / operation only."

changedInput schema / properties / distance_km / description

Previous value: -"Transport distance in kilometres — you provide it; the tool does not route"New value: +"Transport distance in kilometres — you provide it; the tool does not route."

changedInput schema / properties / mass / description

Previous value: -"Shipment mass, expressed in mass_unit. Example: 1000"New value: +"Shipment mass, expressed in mass_unit. Example: 1000."

changedInput schema / properties / mass_unit / description

Previous value: -"Unit for mass (default: kg)"New value: +"Unit for mass. Default: kg."

changedInput schema / properties / mode / description

Previous value: -"Transport mode"New value: +"Transport mode."

addedOutput schema / properties / _source / properties / checked
```
Added value: +{
+  "type": "string"
+}
```
removedOutput schema / properties / _source / properties / computed_by
```
Removed value: -{
-  "type": "string"
-}
```

removedOutput schema / properties / _source / properties / factor

Removed value: -{
-  "additionalProperties": false,
-  "properties": {
-    "authority": {
-      "type": "string"
-    },
-    "basis": {
-      "type": "string"
-    },
-    "edition": {
-      "type": "string"
-    },
-    "last_verified": {
-      "type": "string"
-    },
-    "licence": {
-      "type": "string"
-    },
-    "source_url": {
-      "type": "string"
-    },
-    "unit": {
-      "type": "string"
-    },
-    "value": {
-      "type": "number"
-    }
-  },
-  "required": [
-    "authority",
-    "edition",
-    "value",
-    "unit",
-    "basis",
-    "last_verified",
-    "source_url",
-    "licence"
-  ],
-  "type": "object"
-}

addedOutput schema / properties / _source / properties / name
```
Added value: +{
+  "type": "string"
+}
```

addedOutput schema / properties / _source / properties / provenance_status

Added value: +{
+  "enum": [
+    "verified",
+    "pending-verification",
+    "computed",
+    "live"
+  ],
+  "type": "string"
+}

removedOutput schema / properties / _source / properties / reference
```
Removed value: -{
-  "type": "string"
-}
```
removedOutput schema / properties / _source / properties / standard
```
Removed value: -{
-  "type": "string"
-}
```
removedOutput schema / properties / _source / properties / type
```
Removed value: -{
-  "type": "string"
-}
```

changedOutput schema / properties / _source / required

Previous value: -[
-  "type",
-  "standard",
-  "reference",
-  "source_url",
-  "computed_by",
-  "factor"
-]New value: +[
+  "name",
+  "checked",
+  "provenance_status"
+]

removedOutput schema / properties / available
```
Removed value: -{
-  "type": "boolean"
-}
```

removedOutput schema / properties / available_for

Removed value: -{
-  "additionalProperties": false,
-  "properties": {
-    "modes": {
-      "items": {
-        "type": "string"
-      },
-      "type": "array"
-    },
-    "regions_for_mode": {
-      "items": {
-        "type": "string"
-      },
-      "type": "array"
-    },
-    "sub_modes": {
-      "items": {
-        "additionalProperties": false,
-        "properties": {
-          "id": {
-            "type": "string"
-          },
-          "region": {
-            "type": "string"
-          },
-          "sub_mode": {
-            "type": "string"
-          }
-        },
-        "required": [
-          "region",
-          "id",
-          "sub_mode"
-        ],
-        "type": "object"
-      },
-      "type": "array"
-    }
-  },
-  "required": [
-    "modes",
-    "regions_for_mode",
-    "sub_modes"
-  ],
-  "type": "object"
-}

addedOutput schema / properties / blocking_errors

Added value: +{
+  "items": {
+    "additionalProperties": false,
+    "properties": {
+      "code": {
+        "type": "string"
+      },
+      "message": {
+        "type": "string"
+      },
+      "recovery": {
+        "additionalProperties": false,
+        "properties": {
+          "action": {
+            "type": "string"
+          },
+          "params": {
+            "additionalProperties": {},
+            "type": "object"
+          },
+          "tool": {
+            "type": "string"
+          }
+        },
+        "required": [
+          "action"
+        ],
+        "type": "object"
+      }
+    },
+    "required": [
+      "code",
+      "message",
+      "recovery"
+    ],
+    "type": "object"
+  },
+  "type": "array"
+}

addedOutput schema / properties / citation

Added value: +{
+  "additionalProperties": false,
+  "properties": {
+    "qualifier": {
+      "type": "string"
+    },
+    "text": {
+      "type": "string"
+    }
+  },
+  "required": [
+    "text"
+  ],
+  "type": "object"
+}

addedOutput schema / properties / confidence / additionalProperties
```
Added value: +false
```

addedOutput schema / properties / confidence / properties

Added value: +{
+  "basis": {
+    "enum": [
+      "deterministic",
+      "provenance",
+      "match_quality",
+      "freshness"
+    ],
+    "type": "string"
+  },
+  "level": {
+    "enum": [
+      "high",
+      "medium",
+      "low"
+    ],
+    "type": "string"
+  },
+  "score": {
+    "maximum": 1,
+    "minimum": 0,
+    "type": "number"
+  }
+}

addedOutput schema / properties / confidence / required
```
Added value: +[
+  "level",
+  "basis"
+]
```
changedOutput schema / properties / confidence / type
```
Previous value: -"string"New value: +"object"
```
removedOutput schema / properties / disclaimer
```
Removed value: -{
-  "type": "string"
-}
```

removedOutput schema / properties / emissions

Removed value: -{
-  "additionalProperties": false,
-  "properties": {
-    "basis_used": {
-      "type": "string"
-    },
-    "primary_kgco2e": {
-      "type": "number"
-    },
-    "ttw_kgco2e": {
-      "type": [
-        "number",
-        "null"
-      ]
-    },
-    "wtw_kgco2e": {
-      "type": [
-        "number",
-        "null"
-      ]
-    }
-  },
-  "required": [
-    "wtw_kgco2e",
-    "ttw_kgco2e",
-    "primary_kgco2e",
-    "basis_used"
-  ],
-  "type": "object"
-}

removedOutput schema / properties / empty_running
```
Removed value: -{
-  "type": "string"
-}
```

addedOutput schema / properties / envelope_version

Added value: +{
+  "const": "1",
+  "type": "string"
+}

removedOutput schema / properties / factor

Removed value: -{
-  "additionalProperties": false,
-  "properties": {
-    "authority": {
-      "type": "string"
-    },
-    "edition": {
-      "type": "string"
-    },
-    "id": {
-      "type": "string"
-    },
-    "mode": {
-      "type": "string"
-    },
-    "region": {
-      "type": "string"
-    },
-    "sub_mode": {
-      "type": "string"
-    },
-    "ttw": {
-      "type": [
-        "number",
-        "null"
-      ]
-    },
-    "unit": {
-      "type": "string"
-    },
-    "wtw": {
-      "type": [
-        "number",
-        "null"
-      ]
-    }
-  },
-  "required": [
-    "id",
-    "mode",
-    "sub_mode",
-    "authority",
-    "edition",
-    "region",
-    "unit",
-    "wtw",
-    "ttw"
-  ],
-  "type": "object"
-}

removedOutput schema / properties / inputs

Removed value: -{
-  "additionalProperties": false,
-  "properties": {
-    "basis": {
-      "type": "string"
-    },
-    "distance_km": {
-      "type": "number"
-    },
-    "mass": {
-      "type": "number"
-    },
-    "mass_tonnes": {
-      "type": "number"
-    },
-    "mass_unit": {
-      "type": "string"
-    },
-    "mode": {
-      "type": "string"
-    },
-    "region": {
-      "type": "string"
-    },
-    "sub_mode": {
-      "type": "string"
-    }
-  },
-  "required": [
-    "mass",
-    "mass_unit",
-    "mass_tonnes",
-    "distance_km",
-    "mode",
-    "sub_mode",
-    "region",
-    "basis"
-  ],
-  "type": "object"
-}

removedOutput schema / properties / mass_basis
```
Removed value: -{
-  "type": "string"
-}
```

removedOutput schema / properties / message

Removed value: -{
-  "type": "string"
-}

removedOutput schema / properties / methodology
```
Removed value: -{
-  "type": "string"
-}
```

addedOutput schema / properties / normalized_input

Added value: +{
+  "additionalProperties": {},
+  "type": "object"
+}

addedOutput schema / properties / ok
```
Added value: +{
+  "type": "boolean"
+}
```
removedOutput schema / properties / representativeness
```
Removed value: -{
-  "type": "string"
-}
```

addedOutput schema / properties / result

Added value: +{
+  "anyOf": [
+    {
+      "additionalProperties": true,
+      "properties": {
+        "_source": {
+          "anyOf": [
+            {
+              "additionalProperties": {},
+              "type": "object"
+            },
+            {
+              "type": "null"
+            }
+          ]
+        },
+        "available": {
+          "type": [
+            "boolean",
+            "null"
+          ]
+        },
+        "available_for": {
+          "anyOf": [
+            {
+              "additionalProperties": {},
+              "type": "object"
+            },
+            {
+              "type": "null"
+            }
+          ]
+        },
+        "confidence": {
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "disclaimer": {
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "emissions": {
+          "anyOf": [
+            {
+              "additionalProperties": true,
+              "properties": {
+                "basis_used": {
+                  "type": [
+                    "string",
+                    "null"
+                  ]
+                },
+                "primary_kgco2e": {
+                  "type": [
+                    "number",
+                    "null"
+                  ]
+                },
+                "ttw_kgco2e": {
+                  "type": [
+                    "number",
+                    "null"
+                  ]
+                },
+                "wtw_kgco2e": {
+                  "type": [
+                    "number",
+                    "null"
+                  ]
+                }
+              },
+              "type": "object"
+            },
+            {
+              "type": "null"
+            }
+          ]
+        },
+        "empty_running": {
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "factor": {
+          "anyOf": [
+            {
+              "additionalProperties": true,
+              "properties": {
+                "authority": {
+                  "type": [
+                    "string",
+                    "null"
+                  ]
+                },
+                "edition": {
+                  "type": [
+                    "string",
+                    "null"
+                  ]
+                },
+                "id": {
+                  "type": [
+                    "string",
+                    "null"
+                  ]
+                },
+                "mode": {
+                  "type": [
+                    "string",
+                    "null"
+                  ]
+                },
+                "region": {
+                  "type": [
+                    "string",
+                    "null"
+                  ]
+                },
+                "sub_mode": {
+                  "type": [
+                    "string",
+                    "null"
+                  ]
+                },
+                "ttw": {
+                  "type": [
+                    "number",
+                    "null"
+                  ]
+                },
+                "unit": {
+                  "type": [
+                    "string",
+                    "null"
+                  ]
+                },
+                "wtw": {
+                  "type": [
+                    "number",
+                    "null"
+                  ]
+                }
+              },
+              "type": "object"
+            },
+            {
+              "type": "null"
+            }
+          ]
+        },
+        "inputs": {
+          "anyOf": [
+            {
+              "additionalProperties": {},
+              "type": "object"
+            },
+            {
+              "type": "null"
+            }
+          ]
+        },
+        "mass_basis": {
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "message": {
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "methodology": {
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "representativeness": {
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "summary": {
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "tonne_km": {
+          "type": [
+            "number",
+            "null"
+          ]
+        }
+      },
+      "type": "object"
+    },
+    {
+      "additionalProperties": {},
+      "type": "object"
+    }
+  ]
+}

removedOutput schema / properties / summary

Removed value: -{
-  "type": "string"
-}

removedOutput schema / properties / tonne_km
```
Removed value: -{
-  "type": "number"
-}
```

addedOutput schema / properties / validity

Added value: +{
+  "additionalProperties": false,
+  "properties": {
+    "as_of": {
+      "type": "string"
+    },
+    "effective_from": {
+      "type": "string"
+    },
+    "effective_to": {
+      "type": [
+        "string",
+        "null"
+      ]
+    }
+  },
+  "required": [
+    "as_of"
+  ],
+  "type": "object"
+}

addedOutput schema / properties / warnings

Added value: +{
+  "items": {
+    "additionalProperties": false,
+    "properties": {
+      "code": {
+        "type": "string"
+      },
+      "details": {
+        "additionalProperties": {},
+        "type": "object"
+      },
+      "message": {
+        "type": "string"
+      }
+    },
+    "required": [
+      "code",
+      "message"
+    ],
+    "type": "object"
+  },
+  "type": "array"
+}

changedOutput schema / required

Previous value: -[
-  "available",
-  "methodology",
-  "disclaimer"
-]New value: +[
+  "envelope_version",
+  "ok",
+  "result",
+  "confidence",
+  "_source",
+  "citation"
+]

Changed7 schema fields changedv2.10.1Jun 27, 2026

addedOutput schema / properties / _source / properties / factor / properties / last_verified
```
Added value: +{
+  "type": "string"
+}
```

changedOutput schema / properties / _source / properties / factor / required

Previous value: -[
-  "authority",
-  "edition",
-  "value",
-  "unit",
-  "basis",
-  "source_url",
-  "licence"
-]New value: +[
+  "authority",
+  "edition",
+  "value",
+  "unit",
+  "basis",
+  "last_verified",
+  "source_url",
+  "licence"
+]

addedOutput schema / properties / confidence
```
Added value: +{
+  "type": "string"
+}
```
addedOutput schema / properties / empty_running
```
Added value: +{
+  "type": "string"
+}
```
addedOutput schema / properties / mass_basis
```
Added value: +{
+  "type": "string"
+}
```
addedOutput schema / properties / representativeness
```
Added value: +{
+  "type": "string"
+}
```
addedOutput schema / properties / summary
```
Added value: +{
+  "type": "string"
+}
```

Addedv2.10.0Jun 24, 2026

TDQS

A4.8/5.0

Behavior5/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations cover the safety profile (readOnly, idempotent, non-destructive), yet the description adds substantial context beyond them: deterministic output, empty running already baked into the fleet-average factor, unknown mode/region returning available:false rather than a fabricated factor, rate limiting with reset_at, and basis substitution behavior. This is genuinely rich behavioral disclosure.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Front-loaded with the formula and required inputs, then progressively adds caveats and limitations. It is dense and long, but nearly every sentence carries actionable content (mass_basis warning, no-routing constraint, empty-running note, rate-limit behavior). Not padded, though it could be trimmed marginally.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness5/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a calculator with an output schema, the description still covers the return envelope (wtw/ttw, factor edition, tonne-km, _source), confidence, limitations, and failure modes. Nothing an agent needs to call or interpret it correctly is missing.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters4/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100% and enum values are documented, so the schema carries much of the load. The description still adds real meaning beyond it: mass must be ACTUAL GROSS MASS not chargeable/volumetric weight, distance must be supplied by the caller, and region maps to specific authorities (uk=DEFRA, us=EPA, fr=ADEME). Slightly above baseline.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb (estimate) and resource (freight transport GHG emissions in kgCO2e), gives the exact formula and the ISO 14083 / GLEC v3.2 standard. It also explicitly distinguishes itself from cbm_calculator / ldm_calculator / chargeable_weight_calculator, so an agent can pick it without opening any schema.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines5/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

Explicitly states when to use it (mass + distance + mode, with optional sub_mode/region/basis), when NOT to expect anything (this tool does NOT route, geocode, or compute distances), and names the sibling tools it is distinct from. The alternative-selection rule is fully stated.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.