Turso is an in-process SQL database written in Rust that is compatible with SQLite and also accepts PostgreSQL syntax through an experimental frontend. It is for applications and organizations that need an embeddable database engine with support for multiple languages, platforms, and database features. The catalogue entries are skills and instructions for working with Turso.
Borrowing it
Nothing to install: this file belongs to tursodatabase/turso. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/tursodatabase/turso/main/.claude/skills/differential-fuzzer/SKILL.mdgit clone --depth 1 https://github.com/tursodatabase/tursoWrote 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/tursodatabase/turso/differential-fuzzer)<a href="https://agentmods.dev/skills/tursodatabase/turso/differential-fuzzer"><img src="https://agentmods.dev/badge/skills/tursodatabase/turso/differential-fuzzer/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/tursodatabase/turso/differential-fuzzer"><img src="https://agentmods.dev/badge/skills/tursodatabase/turso/differential-fuzzer.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- Socket pass
- Snyk pass
- 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 MCP Rug Pull · line 58 Docker image references without a specific tag (:latest is implicit) or digest (@sha256:...) can be silently replaced by a malicious image.Fix: Pin the image: image:tag or image@sha256:abc123
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 | $0.00035 | $0.01434 |
| Opus 5 | $0.00017 | $0.00717 |
| Sonnet 5 | $0.00007 | $0.00287 |
| Haiku 4.5 | $0.00003 | $0.00143 |
Grade A, and why
differential-fuzzer 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 — 157 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Differential Fuzzer
Always load Debugging skill for reference
The differential fuzzer compares Turso results against SQLite for generated SQL statements to find correctness bugs.
Location
testing/differential-oracle/fuzzer/
Running the Fuzzer
Single Run
# Basic run (100 statements, random seed)
cargo run --bin differential_fuzzer
# With specific seed for reproducibility
cargo run --bin differential_fuzzer -- --seed 12345
# More statements with verbose output
cargo run --bin differential_fuzzer -- -n 1000 --verbose
# Keep database files after run (for debugging)
cargo run --bin differential_fuzzer -- --seed 12345 --keep-files
# All options
cargo run --bin differential_fuzzer -- \
--seed <SEED> # Deterministic seed
-n <NUM> # Number of statements (default: 100)
-t <NUM> # Number of tables (default: 2)
-c <NUM> # Columns per table (default: 5)
--verbose # Print each SQL statement
--keep-files # Persist .db files to disk
Continuous Fuzzing (Loop Mode)
# Run forever with random seeds
cargo run --bin differential_fuzzer -- loop
# Run 50 iterations
cargo run --bin differential_fuzzer -- loop 50
Docker Runner (CI/Production)
# Build and run from repo root
docker build -f testing/differential-oracle/fuzzer/docker-runner/Dockerfile -t fuzzer .
docker run -e GITHUB_TOKEN=xxx -e SLACK_WEBHOOK_URL=xxx fuzzer
Environment variables for docker-runner:
TIME_LIMIT_MINUTES- Total runtime (default: 1440 = 24h)PER_RUN_TIMEOUT_SECONDS- Per-run timeout (default: 1200 = 20min)NUM_STATEMENTS- Statements per run (default: 1000)LOG_TO_STDOUT- Print fuzzer output (default: false)GITHUB_TOKEN- For auto-filing issuesSLACK_WEBHOOK_URL- For notifications
Output Files
All output goes to simulator-output/ directory:
| File | Description |
|---|---|
test.sql |
All executed SQL statements. Failed statements prefixed with -- FAILED:, errors with -- ERROR: |
schema.json |
Database schema at end of run (or at failure) |
test.db |
Turso database file (only with --keep-files) |
test-sqlite.db |
SQLite database file (only with --keep-files) |
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 · 157 lines · 35 tokens per session scan A a571d647c52d
differential-fuzzer is a skill published in the GitHub repository tursodatabase/turso (24,220 stars, last pushed today), licensed MIT. It adds 35 tokens to every session and 1,434 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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