Master Rust async programming with Tokio, async traits, error handling, and concurrent patterns.
SkillScore95Maintained
Automatic
◆Coding pack
Last verified 8/29/2026
What it changes
Passed 21 of 22 test cases with the skill, and 19 of 22 without it.
Without skill86%
With skill95%
Checks it passed that the model alone missed
Uses CancellationToken to handle graceful worker shutdown.
Stores tokio::sync::SemaphorePermit inside the connection guard struct.
Uses tracing macros for logging during server lifecycle instead of println!.
2 fixed19 passed either way1 still failing0 broke
Pass-rate lift
+9 pp
Tokens
+117%
Agent turns
0%
Response time
-16%
Model gemini-3.6-flashMeasured 8/29/2026v121 of 22 cases passed with skill
Tokens, turns and time describe resource use, not a dollar price.
See it in action
One of 2 test cases the skill fixed. Same model, same prompt, with and without the skill.
1 of 2
Prompt
Can you write a Tokio-based background server runner in Rust that spawns worker loops to process incoming work? It needs to cleanly handle a Ctrl+C termination signal, notify all running worker routines to stop their current loops, wait for pending cleanup operations, and exit cleanly. Please include code for both the runner function and a sample worker loop structure.
What was checked, without and with the skill
Checked
Without skill
With skill
Uses CancellationToken to handle graceful worker shutdown.
Missed
Passed
Uses tracing macros for logging during server lifecycle instead of println!.
Missed
Passed
case-01 · gemini-3.6-flash · 8/29/2026 · answers are capped and redacted
What's inside
The instructions your model reads when the skill loads.
SKILL.md514 linessingle file
Rust Async Patterns
Production patterns for async Rust programming with Tokio runtime, including tasks, channels, streams, and error handling.