Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx skills add rrezartprebreza/spring-boot-skills --skill spring-boot-migrationgit clone --depth 1 https://github.com/rrezartprebreza/spring-boot-skillsWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/skills/rrezartprebreza/spring-boot-skills/spring-boot-migration)<a href="https://agentmods.dev/skills/rrezartprebreza/spring-boot-skills/spring-boot-migration"><img src="https://agentmods.dev/badge/skills/rrezartprebreza/spring-boot-skills/spring-boot-migration/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/skills/rrezartprebreza/spring-boot-skills/spring-boot-migration"><img src="https://agentmods.dev/badge/skills/rrezartprebreza/spring-boot-skills/spring-boot-migration.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector pass
What it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00045 | $0.00559 |
| Opus 5 | $0.00023 | $0.00280 |
| Sonnet 5 | $0.00009 | $0.00112 |
| Haiku 4.5 | $0.00005 | $0.00056 |
Grade A, and why
spring-boot-migration scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 10d ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
How it starts
The opening of the file, as written. The whole thing — 55 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Spring Boot 3 to 4 Migration
Migrate in controlled stages. Keep behavior changes separate from the framework upgrade.
Establish the baseline
- Upgrade to the latest Boot 3.5 maintenance release.
- Run unit, slice, integration, startup, and migration tests before changing the major version.
- Remove Boot 3 deprecations and record all explicitly versioned dependencies.
- Compare the Boot 3.5 and Boot 4 dependency-management reports.
- Verify Spring Cloud and other portfolio release-train compatibility independently.
Prepare for Boot 4
- Require Java 17 or newer; prefer Java 21 for application builds.
- Replace
javax.*remnants with Jakarta APIs before the upgrade. - Remove Undertow assumptions; Boot 4 requires a Servlet 6.1-compatible container.
- Inventory Jackson 2 custom modules, serializers,
ObjectMapperbeans, and package imports. - Inventory test annotations, especially
@MockBean,@SpyBean, and implicit MockMvc setup. - Add
spring-boot-properties-migratortemporarily after changing the Boot version, then remove it.
Migrate dependencies deliberately
Boot 4 is more modular. Prefer dedicated starters over relying on incidental transitive dependencies. Expect dedicated starters for web MVC, security tests, Flyway/Liquibase, and technology-specific tests. Use the classic starters only as a temporary diagnostic bridge, never as the final dependency model.
Verify the result
- Run the application with every supported profile.
- Exercise schema migration against a production-like database copy.
- Verify JSON contracts, security failures, pagination, and error responses.
- Confirm actuator exposure, logging, metrics, and tracing behavior.
- Remove the properties migrator and all classic starters before declaring the migration complete.
Examples
- See
examples/good-migration-plan.mdfor a staged migration. - See
examples/bad-migration-plan.mdfor a risky one-step upgrade.
Gotchas
- Agent jumps from an old Boot 3 minor directly to Boot 4 - upgrade to current 3.5 first.
- Agent changes framework versions and business behavior together - isolate the migration diff.
- Agent assumes all Boot 3 starters keep the same names and transitive dependencies - audit each one.
- Agent leaves
spring-boot-properties-migratorin production - remove it after configuration cleanup. - Agent treats passing compilation as completion - verify runtime wiring, JSON, security, and tests.
What ships with it
3 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 10d ago First seen · 55 lines · 45 tokens per session scan A 105542f5a492
spring-boot-migration is a skill published in the GitHub repository rrezartprebreza/spring-boot-skills (260 stars, last pushed 2d ago), licensed MIT. It adds 45 tokens to every session and 559 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.
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