Retrieve the active EV charging session to check available power, battery level, time remaining, and cost. Monitor charging progress and expenses from vehicle data.
Get the active charging session, including available power, battery level, time remaining and cost.
| Name | Required | Description | Default |
|---|---|---|---|
No arguments | |||
Changes observed during successful MCP inspections.
v1.9.3Input schema / $schemaRemoved value: -"http://json-schema.org/draft-07/schema#"v1.5.4Input schema / additionalPropertiesRemoved value: -falseInput schema / properties / vehicle_idRemoved value: -{
- "description": "Vehicle ID from your account info",
- "type": "string"
-}Input schema / requiredRemoved value: -[
- "vehicle_id"
-]v1.0.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered. The description adds the useful detail that this targets the currently active session and lists returned data, but says nothing about behavior when no session is active, auth requirements, or latency/rate limits.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
A single tight sentence with the key qualifier ('active') and return payload front-loaded. Nothing is wasted, though it is minimal enough that it could have absorbed one routing clause at no cost.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
For a zero-parameter, read-only tool with no output schema, the description usefully enumerates the returned fields (power, battery level, time remaining, cost). The only gap is not stating what happens when there is no active session.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
The tool takes zero parameters, so there is nothing for the description to disambiguate; baseline 4 applies. The listed return fields are a small bonus but are not parameter semantics.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
States a specific verb (Get) and resource (active charging session) and enumerates the returned fields, which distinguishes it from the history and schedule siblings. It never names those siblings explicitly, so the differentiation is inferential rather than stated.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
The word 'active' implies this is for the current session rather than past sessions or schedules, which is weak implicit guidance. There is no explicit when-to-use, when-not-to-use, or pointer to rivian_get_charging_history / rivian_get_charging_schedule.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.