Calculate the light-year distance between two Elite Dangerous star systems using live EDSM coordinates, and estimate the number of jumps for a given jump range.
Light-year distance between two systems (live EDSM coords) + jump estimate.
| Name | Required | Description | Default |
|---|---|---|---|
| to_system | Yes | ||
| from_system | Yes | ||
| jump_range_ly | No |
| Name | Required | Description | Default |
|---|---|---|---|
No arguments | |||
Changes observed during successful MCP inspections.
v0.2.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are supplied, so the description carries the full burden. It does disclose useful behavior beyond the name: coordinates come live from EDSM (implying an external network call and possible latency/failure) and a jump estimate is returned. It does not say what happens when a system name is unknown, or how the estimate degrades when jump range is unset.
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 front-loaded sentence with no filler, and the primary output (distance) precedes the secondary (jump estimate). It is terse to the point of under-specification, but nothing extraneous is present.
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?
An output schema exists, so return values need not be explained, and the core purpose is covered. Still, for a three-parameter tool with zero schema descriptions and no annotations, the definition leaves input formats and edge-case behavior unaddressed.
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?
Schema description coverage is 0% across three parameters, and the description only obliquely explains jump estimation. It never clarifies whether from_system/to_system are names versus IDs, nor what jump_range_ly=0 (the default) means for the jump estimate.
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?
The description states a specific computation (light-year distance between two named systems) and adds a secondary output (jump estimate), plus the data source (live EDSM coords). That is enough to separate it from siblings like spansh_query_systems or edsm_sphere_systems, which query sets of systems rather than measuring a pair.
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?
There is no statement of when to use this tool versus alternatives such as edsm_system_info or spansh_find_nearby_stations, and no note on prerequisites (e.g., both systems must exist in EDSM). The agent must infer the routing decision from the one-line purpose alone.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.