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

With only readOnlyHint=false as structured coverage, the description carries the full burden and discharges it richly: jump time formula, fuel cost scaling with mass and speed, Pathfinder module requirement, one-time fuel cost, asynchronous return with polling via get_location, drift/drop-out behavior, and the 5x redirect cost. This is exactly the behavioral context annotations do not provide.

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?

Core purpose is front-loaded, but the body is a dense ~350-word block with parenthetical asides and a rhetorical closer ("Getting the timing right is the hard part.") that doesn't aid invocation. Several sentences about reverse-ray reasoning could be compressed without losing actionable content.

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 complex mutation tool with no output schema, the description covers requirements, cost model, timing, asynchronous behavior and how to observe results (poll get_location), plus edge cases like wormhole targeting and redirects. An agent has everything needed to invoke it correctly.

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 coverage is 100% so baseline is 3, but the description goes beyond the schema by explaining the bearing convention (0 = +X galactic axis, counter-clockwise, atan2 formula using get_map coordinates) and the distinction between charted wormhole IDs and unknown_system targets. That adds real semantic value over the schema text.

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 opening sentence states a specific verb (jump) and resource (adjacent star system) and immediately names the second mode (numeric bearing with a Pathfinder Drive). This distinguishes it from siblings like travel, find_route, and get_system without needing to open any schema.

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?

It gives clear conditional guidance: use get_system to see connected systems, a wormhole POI ID is a valid target once charted, numeric bearings require a Pathfinder Drive module, and self_destruct is the last resort when out of fuel. It does not explicitly contrast against the travel sibling for in-system movement, so it stops short of full when/when-not routing.

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