What is ajmx?#

ajmx is a JMX CLI for AI agents, to inspect and control a running JVM. It lists local JVMs and searches, describes, reads, writes and invokes MBeans on local and remote JVMs.

Why#

To look inside a running JVM, such as its heap, threads, connection pools or log levels, an agent has to go through JMX. The usual JMX tools are made for people. JDK Mission Control, VisualVM and jconsole are GUIs, and jmxterm prints text meant to be read, not parsed.

ajmx reads or changes a JVM in one command and prints the result as one JSON document.

Zero setup.

--pid connects to a local JVM even without remote JMX enabled. No JVM flags and no restart, so you can look at a problem while it is still happening.

Only JSON.

Every result is one JSON document, and so is every error. error.code and retryable tell the agent what happened and whether to try again, with no stack trace to interpret.

Always bounded.

--limit and --max-bytes cap the output, so no command fills the agent's context with more than you allow. truncated marks what was cut.

Find, read, change.

An agent needs no MBean names up front. search and describe show what a JVM has, so the agent can work on an application it has never seen.

Single binary.

A native binary. No JVM or daemon required.

Just ask#

Add the agent skill and ask about a running JVM in your own words. The agent finds the JVM and its MBeans, reads them, and changes the JVM only when you ask.

What it looks like#

Terminal

ajmx --pid 12345 read java.lang:type=Memory HeapMemoryUsage

{"schemaVersion":1,"ok":true,"result":{"mbean":"java.lang:type=Memory","attributes":{"HeapMemoryUsage":{"committed":268435456,"init":268435456,"max":268435456,"used":41491160}}},"durationMs":19}

An agent decides on ok and error.code, and reads the values from result. See Output and Errors and exit codes.

Next#

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