turso: Skill for Claude Code

.claude/skills/yield-injections/SKILL.md

yield-injections is a skill for Claude Code from tursodatabase/turso. It costs 82 tokens per session (1,929 once invoked), scanned A, original, MIT.

Test-only machinery for deliberately pausing or failing resumable state machines at selected points. A resumable state machine is code that can continue safely after an interruption.

In plain words
What is it for?
Use it in Turso tests and simulations to inject cooperative pauses or failures around commits, checkpoints, cursors, and state transitions.
Why use it?
It exposes bugs that occur at handoff, checkpoint, commit, or cursor boundaries and helps verify that recovery remains safe.

Skill for Claude Code

Written for Claude Code: installed under .claude/.

This is tursodatabase/turso's own configuration. It tells Claude Code how to work on turso itself, so it is not a mod to install elsewhere. Copy it as a starting point and replace the rules that are about this project. Everything turso configures →

About the project

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.

tursodatabase/turso · 24,209 stars · on GitHub

Reuse

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.

Copy the file
curl -O https://raw.githubusercontent.com/tursodatabase/turso/main/.claude/skills/yield-injections/SKILL.md
Clone the repo
git clone --depth 1 https://github.com/tursodatabase/turso

Made for: Claude Code.

Wrote 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.

agentmods badge for yield-injections

README.md
[![agentmods](https://agentmods.dev/badge/skills/tursodatabase/turso/yield-injections/github.svg)](https://agentmods.dev/skills/tursodatabase/turso/yield-injections)
Your own site
<a href="https://agentmods.dev/skills/tursodatabase/turso/yield-injections"><img src="https://agentmods.dev/badge/skills/tursodatabase/turso/yield-injections/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.

agentmods 80×15 button for yield-injections

Your own site · 80×15
<a href="https://agentmods.dev/skills/tursodatabase/turso/yield-injections"><img src="https://agentmods.dev/badge/skills/tursodatabase/turso/yield-injections.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 82 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,929 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe. Third-party audits
  • Snyk pass 7 Sept 2026
  • NVIDIA SkillSpector pass 7 Sept 2026
How audits are shown
Origin original No closer match found in the catalogue.
Token cost

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.

ModelPer sessionOnce invoked
Fable 5.1 $0.00082 $0.01929
Opus 5 $0.00041 $0.00964
Sonnet 5 $0.00016 $0.00386
Haiku 4.5 $0.00008 $0.00193

Measured 9d ago against content hash 1ef2db605890, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-09, from the pricing page.

Security

Grade A, and why

yield-injections 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 9d 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.

.claude/skills/yield-injections/SKILL.md · 166 lines

How it starts

The opening of the file, as written. The whole thing — 166 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Yield Injection Guide

Yield injection is test-only infrastructure for forcing cooperative-yield or failure boundaries in resumable state machines. The implementation currently lives under core/mvcc/, but the mechanism is not MVCC semantics.

Key Files

  • core/mvcc/yield_points.rs: injector traits and macros.
  • core/mvcc/yield_hooks.rs: YieldPointMarker, YieldContext, ProvidesYieldContext.
  • core/connection.rs: per-connection injector slots and yield_instance_id_counter.
  • core/mvcc/database/mod.rs: commit points and commit cleanup.
  • core/mvcc/database/checkpoint_state_machine.rs: checkpoint points.
  • core/mvcc/cursor.rs: cursor points.
  • core/mvcc/database/tests.rs: fixed test injectors and regression examples.
  • testing/concurrent-simulator/yield_injection.rs: simulator injector.

All hooks are behind cfg(any(test, injected_yields)); injected_yields means test_helper or simulator.

Core Model

YieldPoint { ordinal, point_count } identifies one hook in one point family. Families are #[repr(u8)] enums implementing YieldPointMarker; ordinal is source-order self as u8, and point_count comes from EnumCount.

Do not reorder existing yield-point variants. Simulator plans store raw ordinals, not names.

Why reordering matters: ordinal is self as u8, so source order is part of the deterministic schedule. If a seed planned "yield at ordinal 2", reordering can silently retarget that same seed from one conceptual hook to another. This makes CI seeds, bisects, and simulator coverage hard to reproduce. Appending a variant still changes point_count and can perturb future plans, but it preserves the meaning of existing ordinals.

Each yield-capable live object has:

  • instance_id: distinguishes simultaneous state machines/cursors.
  • selection_key: stable logical-operation key used by deterministic plans.
  • active connection injectors: yield_injector() and failure_injector().

Hook Macros

  • inject_transition_yield!(self, Point): for StateTransition returning TransitionResult<T>.
  • inject_io_yield!(self, Point): for cursor/helper functions returning IOResult<T>.
  • inject_transition_failure!(self, Point): returns Err(LimboError) from StateTransition.

Read the full file on GitHub · 166 lines

Changes

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.

  1. 9d ago First seen · 166 lines · 82 tokens per session scan A 1ef2db605890

Subscribe to this mod's changes

yield-injections is a skill published in the GitHub repository tursodatabase/turso (24,209 stars, last pushed today), licensed MIT. It adds 82 tokens to every session and 1,929 once invoked, about $0.0004 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.

Related

Other skills, from other repositories

chdb-datastore

Use when the user has tabular data (pandas DataFrame, parquet, csv, Arrow, json) and wants to filter, group, aggregate, join, or speed up slow pandas. Provides chDB DataStore — same pandas API, ClickHouse engine underneath. Also handles reading from S3, MySQL, PostgreSQL, MongoDB, ClickHouse Cloud, Iceberg, Delta Lake…

chdb-io/chdb · 168 tokens

chdb-sql

Use when the user wants to run SQL — especially analytical SQL — on local files (parquet/csv/json), URLs, S3 paths, or remote databases (Postgres, MySQL, MongoDB, ClickHouse Cloud, Iceberg, Delta Lake) without setting up a server. Provides chDB — embedded ClickHouse SQL in Python with 1000+ functions, Session for…

chdb-io/chdb · 214 tokens

dbt-expert

Expert-level dbt (data build tool), models, tests, documentation, incremental models, macros, and Jinja templating. Use when the user mentions analytics engineering, SQL, data transformation, Jinja, or testing, or when the task involves Project Structure and Configuration, Sources and Staging Models, Intermediate and…

personamanagmentlayer/pcl · 76 tokens

sql-development

T-SQL, stored procedures, and MS SQL Server DBA practices. Use when writing SQL queries, designing schemas, tuning SQL Server performance, managing backups, configuring security, or using SQL Server 2025+ features.

PracticalSwan/agent-skills · 47 tokens

ui-visual-regression

Automates visual regression testing for DB Console UI changes. Compares screenshots and network requests between the current branch and its merge base using roachprod, playwright-cli, and ImageMagick. Use when the user wants to verify UI changes haven't introduced visual or behavioral regressions.

cockroachdb/cockroach · 61 tokens

dbt

Operational skill for dbt: models, refs, tests, docs, and analytics engineering workflows on warehouses.

alivirgo/Major-AI-Skills · 24 tokens