15 tools from the Javaperf MCP Server, categorised by risk level.
View the Javaperf policy →analyze_threads Produces a thread dump of the specified Java process (equivalent to jstack -l). Shows each thread's name, state, and full stack trace with lock inf... check_deadlock Checks for Java-level deadlocks in the specified process. Parses jcmd Thread.print output and returns structured JSON: which threads are involved, ... heap_dump Creates a heap dump (.hprof file) for offline analysis in Eclipse MAT, VisualVM, or JProfiler. Saved to recordings/heap_dump.hprof (overwritten eac... heap_histogram Class histogram of live objects in the heap (jcmd GC.class_histogram). Returns top classes by memory usage — useful for memory leak investigation. ... heap_info Brief heap usage summary: capacities, used, committed regions. Quick snapshot without full dump. list_java_processes Lists all running Java processes on the machine. Returns an array of objects with pid, mainClass, and args. Use this tool first to discover the tar... list_jfr_recordings Lists active and recent JFR recordings for a Java process (jcmd JFR.check). Returns recording id, duration, state (running/stopped), and filename. ... profile_frequency Call frequency profile from a .jfr file. Counts methods that appear at the leaf (top) of the stack in ExecutionSample events — i.e. methods that we... profile_memory Memory-focused profile from a .jfr file. Returns top memory allocators (class+method), GC statistics, and potential leak candidates from OldObjectS... profile_time CPU time (bottleneck) profile from a .jfr file. Uses bottom-up aggregation: each method is counted in every sample where it appears in the stack, i... 2/5 trace_method Builds a call tree for a specific method from a .jfr file. Filters ExecutionSample events to find stack traces containing the given class and metho... vm_info JVM information: uptime, version, and flags. Useful for environment verification. parse_jfr_summary Parses a .jfr file and returns a structured summary: top methods by CPU samples, GC statistics, thread allocation stats, and anomaly hints (e.g. hi... 4/5 start_profiling Starts a Java Flight Recorder (JFR) recording on the specified Java process. Uses settings=profile for a full dump. Before starting, rotates files:... 3/5 stop_profiling Stops an active JFR recording and saves it to recordings/new_profile.jfr. Use recordings/new_profile.jfr for current data, recordings/old_profile.j... 3/5 The Javaperf MCP server exposes 15 tools across 2 categories: Read, Execute.
Use Intercept, the open-source MCP proxy. Write YAML rules for each tool — rate limits, argument validation, or deny rules — then run Intercept in front of the Javaperf server.
Javaperf tools are categorised as Read (12), Execute (3). Each category has a recommended default policy.
Open source. One binary. Zero dependencies.
npx -y @policylayer/intercept