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 ariaramin/flutter-skills --skill flutter-hive-persistence-engineeringgit clone --depth 1 https://github.com/ariaramin/flutter-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/ariaramin/flutter-skills/flutter-hive-persistence-engineering)<a href="https://agentmods.dev/skills/ariaramin/flutter-skills/flutter-hive-persistence-engineering"><img src="https://agentmods.dev/badge/skills/ariaramin/flutter-skills/flutter-hive-persistence-engineering/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/ariaramin/flutter-skills/flutter-hive-persistence-engineering"><img src="https://agentmods.dev/badge/skills/ariaramin/flutter-skills/flutter-hive-persistence-engineering.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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 | $0.00131 | $0.04390 |
| Opus 5.5 | $0.00052 | $0.01756 |
| Sonnet 5.5 | $0.00026 | $0.00878 |
| Haiku 4.5 | $0.00013 | $0.00439 |
Grade A, and why
flutter-hive-persistence-engineering 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 22d 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 — 494 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Flutter Hive Persistence Engineering
Mission
Treat Hive/Hive CE persistence as a long-lived data contract, not a transient implementation detail. Use this loop:
Classify data/access pattern
→ inspect deployed storage contract
→ choose storage/box/model strategy
→ design compatibility + recovery
→ implement smallest safe change
→ test old persisted data + failures
→ measure startup/memory/storage/write cost
Highest-priority invariant:
Persisted data is part of the application's long-lived external contract. A Dart model change is not safe merely because the new code compiles.
Operating Rules
- Inspect pinned package versions and existing storage before editing persistence.
- Treat box names, key formats, type IDs, field IDs, encryption configuration, and generated schema metadata as migration-sensitive.
- Never reuse a retired type ID for a different persisted type.
- Never renumber existing field IDs for aesthetics or source-order cleanup.
- Design migrations before shipping incompatible schema changes.
- Make migrations sequential, restartable/idempotent, validated, and historical-fixture tested.
- Commit the schema version only after validation succeeds.
- Preserve valuable source data until the replacement is safely written and validated.
- Register adapters deterministically before opening boxes containing those types.
- Open boxes through a deliberate owner and reuse them;
openBoxis lifecycle configuration, not a query. - Keep Hive details behind repository/local-data boundaries in nontrivial applications.
- Choose
Box<T>vsLazyBox<T>from measured memory and access patterns. - Do not force relational/query-heavy workloads into Hive.
- Await important writes; do not assume arbitrary multi-record/cross-box operations are atomic.
- Keep Hive encryption keys outside Hive, normally in platform-secure storage.
- Do not store high-value credentials in ordinary Hive merely because it is convenient.
- Recover differently for disposable cache, reconstructable data, and critical local user data.
- Never delete valuable storage as generic exception handling.
- Debounce/batch high-frequency writes and persist critical edits before termination.
- Use Hive CE
IsolatedHiveonly when supported multi-isolate persistence is genuinely required. - Treat Flutter Web as browser/IndexedDB persistence with different durability and security semantics.
- Preserve Hive CE generated schema metadata in version control.
- Separate package migration from schema redesign when valuable production data exists.
- Re-run historical compatibility tests after adapter, generator, encryption, or package changes.
What ships with it
5 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.
- 22d ago First seen · 494 lines · 131 tokens per session scan A cb672cbc85b2
flutter-hive-persistence-engineering is a skill published in the GitHub repository ariaramin/flutter-skills (8 stars, last pushed 2d ago), licensed MIT. It adds 131 tokens to every session and 4,390 once invoked, about $0.0005 per session on Opus 5.5. 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 2026-10-11.
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