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 johnqtcg/awesome-skills --skill mongo-migrationgit clone --depth 1 https://github.com/johnqtcg/awesome-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/johnqtcg/awesome-skills/mongo-migration)<a href="https://agentmods.dev/skills/johnqtcg/awesome-skills/mongo-migration"><img src="https://agentmods.dev/badge/skills/johnqtcg/awesome-skills/mongo-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/johnqtcg/awesome-skills/mongo-migration"><img src="https://agentmods.dev/badge/skills/johnqtcg/awesome-skills/mongo-migration.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector warn
SkillSpector: 1 finding, up to medium
These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →
- medium Excessive Agency · line 161 Skill enables autonomous high-impact decisions without human-in-the-loop verification. Critical operations (destructive commands, financial transactions, data deletion) should require explicit user confirmation.Fix: Add human-in-the-loop confirmation for destructive, irreversible, or high-impact operations. Never auto-execute commands that modify files, send data, or alter system state.
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 | $0.00140 | $0.05410 |
| Opus 5.5 | $0.00056 | $0.02164 |
| Sonnet 5.5 | $0.00028 | $0.01082 |
| Haiku 4.5 | $0.00014 | $0.00541 |
Grade A, and why
mongo-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 1mo 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 — 369 lines — stays where its author put it; the contents beside it link to each section on GitHub.
MongoDB Migration Safety Review
Quick Reference
| If you need to… | Go to |
|---|---|
| Understand what this skill covers | §1 Scope |
| Check mandatory prerequisites | §2 Mandatory Gates |
| Choose review depth | §3 Depth Selection |
| Handle incomplete context | §4 Degradation Modes |
| Analyze migration safety item by item | §5 Migration Safety Checklist |
| Design a phased execution plan | §6 Execution Plan |
| Avoid common migration mistakes | §7 Anti-Examples |
| Score the review result | §8 Scorecard |
| Format review output | §9 Output Contract |
| Look up index/DDL lock behavior | references/mongo-ddl-lock-matrix.md |
| Plan a large-collection migration | references/large-collection-migration.md |
§1 Scope
In scope — schema migration safety for MongoDB 7.0 and 8.0, the releases still in support as of 2026-08. 4.4, 5.0 and 6.0 have reached end of life; if a user names one, say so before reviewing, because an EOL server receives no security fixes and the version-gated advice below assumes 7.0+:
- Document schema evolution (add/remove/rename/retype fields)
- Index operations (createIndex, dropIndex, replicated vs rolling builds, TTL indexes)
- Schema validator changes (collMod with JSON Schema validation)
- Data backfill and transformation (aggregation pipeline updates, bulkWrite)
- Shard key changes (reshardCollection 5.0+, refineCollectionShardKey 4.4+)
- Migration script review (mongosh scripts, application-driven migrations)
- Write concern / read concern tuning during migration phases
- Rollback planning (MongoDB's DDL is mostly non-transactional — but see §5.3 item 10: createCollection and createIndex do work inside a transaction)
What ships with it
29 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.
- references/large-collection-migration.md 23 KB
- references/migration-anti-examples.md 4.3 KB
- references/mongo-ddl-lock-matrix.md 7.8 KB
- scripts/lint_migration.py 29 KB runs code
- scripts/mongo_server_harness.sh 8.0 KB runs code
- scripts/mutation_sweep.py 17 KB runs code
- scripts/run_regression.sh 6.3 KB runs code
- scripts/tests/COVERAGE.md 8.4 KB
- scripts/tests/golden/001_unbounded_update.json 1.3 KB
- scripts/tests/golden/002_no_write_concern.json 1.3 KB
- scripts/tests/golden/003_no_rollback.json 1.3 KB
- scripts/tests/golden/004_validator_strict_before_backfill.json 1.3 KB
- scripts/tests/golden/005_unique_index_no_dupe_check.json 1.2 KB
- scripts/tests/golden/006_inplace_type_change.json 1.2 KB
- scripts/tests/golden/007_well_formed_phased.json 2.8 KB
- scripts/tests/golden/008_good_rolling_index.json 2.1 KB
- scripts/tests/golden/009_degraded_no_context.json 1.2 KB
- scripts/tests/golden/010_field_type_workflow.json 1.4 KB
- scripts/tests/golden/011_foreground_index_large.json 1.6 KB
- scripts/tests/golden/012_reshard_collection.json 1.5 KB
- scripts/tests/golden/013_sharded_bulk_write.json 1.5 KB
- scripts/tests/mongo_server.py 8.7 KB runs code
- scripts/tests/test_go_examples_compile.py 10 KB runs code
- scripts/tests/test_golden_scenarios.py 17 KB runs code
- scripts/tests/test_lint_migration.py 19 KB runs code
- scripts/tests/test_mongo_facts_drift.py 20 KB runs code
- scripts/tests/test_mongo_server_matrix.py 25 KB runs code
- scripts/tests/test_skill_contract.py 15 KB runs code
- scripts/tests/update_coverage_counts.py 4.3 KB runs code
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.
- 1mo ago First seen · 369 lines · 140 tokens per session scan A 180668b4be05
mongo-migration is a skill published in the GitHub repository johnqtcg/awesome-skills (30 stars, last pushed 18d ago), licensed MIT. It adds 140 tokens to every session and 5,410 once invoked, about $0.0006 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 2026-08-30.
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