VesselAPI MCP Server

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get_vessel_emissions

Retrieves EU MRV annual emissions reports for a vessel, including CO2 and fuel consumption data. Use it to check verified emissions for ships reporting under EU MRV.

Instructions

Get EU MRV annual emissions reports for a vessel (CO2, fuel consumption). Only ships that report under EU MRV have data.

Tool call template

Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {
      "vesselId": "<vesselId>"
    },
    "name": "get_vessel_emissions"
  }
}

Input Schema

Name	Required	Description
`limit`	No	Results per page, 1 to 50. Defaults to 20.
`idType`	No	Identifier type: imo (default) or mmsi
`vesselId`	Yes	Vessel identifier (IMO number by default)
`nextToken`	No	Pagination token from previous response

Schema Changelog

Changes observed during successful MCP inspections.

Changed1 schema field changedv2.2.0Oct 30, 2026
- removedInput schema / additionalProperties
```
Removed value: -false
```

Changed6 schema fields changedv2.0.0Aug 20, 2026

changedInput schema / properties / idType / description

Previous value: -"Identifier type: imo (default), mmsi, or vesselId"New value: +"Identifier type: imo (default) or mmsi"

addedInput schema / properties / idType / enum
```
Added value: +[
+  "imo",
+  "mmsi"
+]
```

changedInput schema / properties / limit / description

Previous value: -"Max results per page"New value: +"Results per page, 1 to 50. Defaults to 20."

addedInput schema / properties / limit / maximum
```
Added value: +50
```
addedInput schema / properties / limit / minimum
```
Added value: +1
```

changedInput schema / properties / limit / type

Previous value: -"number"New value: +"integer"

Addedv1.3.0May 6, 2026

TDQS

B3.4/5.0

Behavior3/5

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

With no annotations, the description carries the full burden; it discloses one meaningful behavioral trait — the EU MRV coverage limitation that produces empty results. It says nothing about result volume, ordering, pagination behavior, or whether the call is read-only, leaving the safety and cost profile implied.

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?

Two short sentences with no filler, and the core purpose is front-loaded before the coverage caveat. Nothing is wasted, though there is also nothing beyond the minimum.

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

Completeness3/5

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

For a simple four-parameter read tool with a fully-covered schema and no output schema, the description covers the essentials. It still omits what a report record contains beyond CO2 and fuel consumption, and how results are ordered or paged, which matters for a tool that can return up to 50 reports.

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

Parameters3/5

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

Schema description coverage is 100%, so vesselId, idType, limit and nextToken are already fully documented in the schema. The description adds no format or defaulting detail beyond what the schema states, so the baseline of 3 applies.

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

Purpose4/5

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

States a specific verb and resource — annual EU MRV emissions reports for a vessel, with the returned metrics named (CO2, fuel consumption). It does not explicitly distinguish itself from the sibling list_emissions, so an agent must infer the difference from the name alone.

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

Usage Guidelines3/5

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

"Only ships that report under EU MRV have data" gives a useful precondition for interpreting empty results. However, there is no explicit guidance on when to use this versus list_emissions, nor any note on prerequisites such as which idType to supply.

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