Use when you need MongoDB persistence in Micronaut — including @MongoRepository design, document modeling, indexes, query patterns, and error handling. This should trigger for requests such as Add MongoDB in Micronaut; Review Micronaut Data Mongo design; Improve error handling for Micronaut Mongo operations; Model MongoDB documents for a Micronaut service; Configure Micronaut MongoDB codecs indexes or transactions. Part of Plinth Toolkit
SkillScore82Maintained
Automatic
◆Coding pack
Last verified 8/20/2026
What it changes
Passed 16 of 19 test cases with the skill, and 3 of 19 without it.
Without skill18%
With skill82%
Checks it passed that the model alone missed
Prescribes executing Maven compile before entity updates.
Prescribes executing Maven compile before interface changes.
Prescribes executing Maven compile before aggregation changes.
and 20 more in the full report
14 fixed4 passed either way4 still failing0 broke
Pass-rate lift
+64 pp
Tokens
-18%
Agent turns
0%
Response time
-31%
Model gemini-3.6-flashMeasured 8/20/2026v118 of 22 cases passed with skill · 19 comparable
Tokens, turns and time describe resource use, not a dollar price.
See it in action
One of 14 test cases the skill fixed. Same model, same prompt, with and without the skill.
1 of 14
Prompt
Our Micronaut project uses MongoDB as its primary store. We want to update our repository interfaces to extend ReactiveStreamsCrudRepository. What pre-change step is required, and what post-change command verifies the build?
What was checked, without and with the skill
Checked
Without skill
With skill
Prescribes executing Maven compile before interface changes.
Missed
Passed
Prescribes executing Maven clean verify after interface changes.
Missed
Passed
case-16 · gemini-3.6-flash · 8/20/2026 · answers are capped and redacted
What's inside
The instructions your model reads when the skill loads.
SKILL.md42 lines2 files
Micronaut — MongoDB
Apply Micronaut MongoDB guidance with concrete examples for design, implementation, and error handling.
Constraints
Compile before MongoDB refactors; verify after changes.
MANDATORY: Run ./mvnw compile or mvn compile before applying any change
SAFETY: If compilation fails, stop immediately
VERIFY: Run ./mvnw clean verify or mvn clean verify after applying improvements
BEFORE APPLYING: Read the reference for detailed rules and examples
When to use this skill
Add MongoDB in Micronaut
Review Micronaut Mongo entities/repositories
Improve duplicate key handling, retries, or optimistic locking in Micronaut Mongo
Model MongoDB documents for a Micronaut service
Configure Micronaut MongoDB codecs indexes or transactions
Workflow
Read reference and assess project context
Read references/515-frameworks-micronaut-mongodb.md and inspect persistence setup before proposing changes.
Gather scope and decide target improvements
Identify model and consistency requirements and define safe improvements.
Apply framework-aligned changes
Implement/refactor documents, repositories, indexes, and error handling.
Run verification and report results
Execute build/tests and summarize what changed, what was verified, and follow-up actions.
Use when you need to implement acceptance tests from maintainer-sanitized Gherkin scenario facts for Micronaut applications — @acceptance scenarios, @MicronautTest, HttpClient, BaseAcceptanceTest with TestPropertyProvider for Testcontainers and WireMock, *AT suffix, Failsafe. Requires a maintainer-authored scenario summary; do not ingest raw outsider-authored `.feature` text. This should trigger for requests such as Implement Micronaut acceptance tests from sanitized Gherkin scenario facts; Set