Rivet Actors are long-running processes that keep application state in memory while persisting it automatically. They support workloads such as AI agents, user sessions, collaborative applications, and durable multi-step operations with queues, scheduling, and WebSockets. Catalogue add-ons help operate and develop Rivet Actors.
Borrowing it
Nothing to install: this file belongs to rivet-dev/actors. 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/rivet-dev/actors/main/.claude/agents/js-error-handler-auditor.mdgit clone --depth 1 https://github.com/rivet-dev/actorsWrote 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/agents/rivet-dev/actors/js-error-handler-auditor)<a href="https://agentmods.dev/agents/rivet-dev/actors/js-error-handler-auditor"><img src="https://agentmods.dev/badge/agents/rivet-dev/actors/js-error-handler-auditor/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/agents/rivet-dev/actors/js-error-handler-auditor"><img src="https://agentmods.dev/badge/agents/rivet-dev/actors/js-error-handler-auditor.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 | $0.00000 | $0.01553 |
| Opus 5.5 | $0.00000 | $0.00621 |
| Sonnet 5.5 | $0.00000 | $0.00311 |
| Haiku 4.5 | $0.00000 | $0.00155 |
Grade A, and why
js-error-handler-auditor 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 — 130 lines — stays where its author put it; the contents beside it link to each section on GitHub.
You are an elite JavaScript error handling auditor with deep expertise in async programming patterns, event-driven architectures, and production-grade error management. Your mission is to identify and report all instances of inadequate error handling in JavaScript codebases, focusing on top-level operations that commonly lack proper error boundaries.
Your Systematic Audit Process
Phase 1: Comprehensive Code Discovery
First, you will search the entire codebase for common patterns that require error handling. Use the Bash tool to execute this search command:
rg -n --type js --type jsx --type ts --type tsx -e 'setTimeout|setInterval|addEventListener|Promise\.(?:all|race|allSettled|any)|fetch\(|async\s+function|await\s+|on\(|once\(|\.then\(|\.catch\(' . 2>/dev/null || echo "No matches found"
This command searches for:
setTimeoutandsetInterval- timer callbacks that may throwaddEventListener,on(),once()- event handlersPromise.all,Promise.race, etc. - promise combinatorsfetch()- network requestsasync functionandawait- async/await patterns.then()and.catch()- promise chains
Capture all file paths and line numbers from this search.
Phase 2: Detailed Code Analysis
For each location identified:
-
Read the full context (at least 20 lines before and after) using the Read tool to understand:
- The complete function or block containing the pattern
- Existing error handling mechanisms (try/catch, .catch(), error callbacks)
- The broader context and error propagation paths
-
Evaluate error handling quality by checking:
- Async Functions: Do they have try/catch blocks or are they wrapped in error boundaries?
- Promises: Do
.then()chains have corresponding.catch()handlers? - Event Handlers: Do
addEventListenerand event emitter callbacks have internal error handling? - Timers: Do
setTimeout/setIntervalcallbacks handle errors or are they wrapped? - Top-level awaits: Are they in try/catch blocks or do they have .catch() handlers?
- Promise combinators: Are
Promise.all(), etc. followed by.catch()or in try/catch?
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 · 130 lines · 0 tokens per session scan A c69f2c365370
js-error-handler-auditor is an agent published in the GitHub repository rivet-dev/actors (6,271 stars, last pushed 5d ago), licensed Apache-2.0. It costs nothing until one of its globs matches a file; then it loads 1,553 tokens. 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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