What is resonate-basic-debugging-java?

A troubleshooting guide for Resonate applications written with Java. Resonate runs tasks reliably across failures and restarts, while Java 21 is the required Java version here.

Use it to investigate workflows that stop or do not resume, duplicate actions after recovery, unexpected numeric types, command-line argument errors, and Java version or threading issues.

It helps identify problems at the point where Java code connects to durable task execution, such as stalled workflows, replayed side effects, and type decoding.

resonate-basic-debugging-java — Skill by resonatehq/resonate-skills

Install

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.

Any agent

npx skills add resonatehq/resonate-skills --skill resonate-basic-debugging-java

Clone the repo

git clone --depth 1 https://github.com/resonatehq/resonate-skills

Made for: Claude Code, Codex.

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.

README.md

[![agentmods](https://agentmods.dev/badge/skills/resonatehq/resonate-skills/resonate-basic-debugging-java/github.svg)](https://agentmods.dev/skills/resonatehq/resonate-skills/resonate-basic-debugging-java)

Your own site

<a href="https://agentmods.dev/skills/resonatehq/resonate-skills/resonate-basic-debugging-java"><img src="https://agentmods.dev/badge/skills/resonatehq/resonate-skills/resonate-basic-debugging-java/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.

Your own site · 80×15

<a href="https://agentmods.dev/skills/resonatehq/resonate-skills/resonate-basic-debugging-java"><img src="https://agentmods.dev/badge/skills/resonatehq/resonate-skills/resonate-basic-debugging-java.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 104 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.

When invoked 3,093 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.

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.

Model	Per session	Once invoked
Fable 5.1	$0.00104	$0.03093
Opus 5.5	$0.00042	$0.01237
Sonnet 5.5	$0.00021	$0.00619
Haiku 4.5	$0.00010	$0.00309

Measured 1mo ago against content hash c18ca7ebddf4, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

resonate-basic-debugging-java 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.

resonate-basic-debugging-java/SKILL.md · 234 lines

How it starts

The opening of the file, as written. The whole thing — 234 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Resonate Basic Debugging — Java

Prerelease note. resonate-sdk-java is published on Maven Central — pin io.resonatehq:resonate-sdk-java:0.1.1. The API mirrors the Python SDK and may change before a stable 1.0. Requires Java 21+ — the SDK uses virtual threads, a feature generally available in Java 21. Every code block here is compile-verified against 0.1.1 with a Java 21 toolchain, and cross-checked against the resonatehq-examples/*-java repos and develop/java.mdx (docs PR #230).

Overview

Java's type system catches many bugs at compile time — typed method references and a typed ResonateHandle close off whole classes of error the dynamically-typed SDKs hit. The traps that remain are mostly at the durability boundary: untyped-handle decoding, CLI argument binding, replay double-fires, and the by-name-only constraints. This skill is a symptom-first guide to those failure modes.

For the language-agnostic replay and recovery mental model, read durable-execution first.

Triage flow

Does it even build / start? Confirm a Java 21+ toolchain — the SDK uses virtual threads and will not run on Java 8/11/17.
Is the worker connected? Confirm the builder's url(...) (or RESONATE_URL) points at a running server, and r was built without throwing.
Is the function registered? By-name dispatch (rpc, the CLI) needs r.register(Owner::fn) on the executing group.
Is the promise stuck? Run resonate promise get <id> to check state (pending / resolved / rejected / timedout).
Is the workflow replaying but producing duplicates? An un-checkpointed side effect is re-running above a durable boundary.
Is a CLI-invoked function arity-mismatching? Each --arg binds to one positional parameter.
Is the worker up but not picking up work? r.stop() may have been called on a live worker.

Stuck / never-resuming workflows

Latent promise never settled

Symptom: future.await() blocks indefinitely; resonate promise get <id> shows state pending.

Read the full file on GitHub · 234 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.

1mo ago First seen · 234 lines · 104 tokens per session scan A c18ca7ebddf4

Subscribe to this mod's changes

resonate-basic-debugging-java is a skill published in the GitHub repository resonatehq/resonate-skills (7 stars, last pushed 2mo ago), licensed Apache-2.0. It adds 104 tokens to every session and 3,093 once invoked, about $0.0004 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 2026-08-31.

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