OTel Log Beautifier

Beautifies OpenTelemetry JSON structured logs directly in the VS Code integrated terminal. No piping, no separate panels, no modified run commands. Open a terminal, run your service, and JSON log lines become colorized, structured output automatically.

Before / After

Before — raw NDJSON from an OpenTelemetry-instrumented service:

{"timestamp":"2026-04-11T22:51:12.800Z","level":"info","message":"Request received","severity_number":9,"severity_text":"INFO","resource":{"service.name":"api-gateway","service.version":"1.4.0","deployment.environment":"production"},"context":{"requestId":"req_7f3a2b1c","userId":"usr_a8d4e9","path":"/v1/orders"}}
{"timestamp":"2026-04-11T22:51:12.912Z","level":"info","message":"Order validated","severity_number":9,"severity_text":"INFO","resource":{"service.name":"api-gateway","service.version":"1.4.0","deployment.environment":"production"},"context":{"requestId":"req_7f3a2b1c","orderId":"ord_bf82c4","itemCount":3}}
{"timestamp":"2026-04-11T22:51:13.204Z","level":"warn","message":"Payment gateway slow response","severity_number":13,"severity_text":"WARN","resource":{"service.name":"api-gateway","service.version":"1.4.0","deployment.environment":"production"},"context":{"requestId":"req_7f3a2b1c","gateway":"stripe","elapsedMs":1842}}
{"timestamp":"2026-04-11T22:51:13.567Z","level":"error","message":"Inventory check failed","severity_number":17,"severity_text":"ERROR","resource":{"service.name":"api-gateway","service.version":"1.4.0","deployment.environment":"production"},"context":{"requestId":"req_7f3a2b1c","sku":"SKU-1234","reason":"downstream_timeout"}}

After — same logs, beautified. Timestamps shortened, service name pulled out, context indented, repeated resource blocks suppressed, level colors (dim for INFO, yellow for WARN, red for ERROR):

22:51:12.800  INFO   [api-gateway]  Request received
    requestId: req_7f3a2b1c
    userId:    usr_a8d4e9
    path:      /v1/orders

22:51:12.912  INFO   [api-gateway]  Order validated
    requestId:  req_7f3a2b1c
    orderId:    ord_bf82c4
    itemCount:  3

22:51:13.204  WARN   [api-gateway]  Payment gateway slow response
    requestId: req_7f3a2b1c
    gateway:   stripe
    elapsedMs: 1842

22:51:13.567  ERROR  [api-gateway]  Inventory check failed
    requestId: req_7f3a2b1c
    sku:       SKU-1234
    reason:    downstream_timeout

Non-JSON output (shell prompts, ls, git status, compiler warnings) passes through unchanged.

Features

• Automatic JSON detection — JSON log lines get formatted, everything else passes through
• Multi-format support — OTel, pino, winston, bunyan, and generic JSON (priority chain: OTel > bunyan > pino > winston > generic)
• Level-based coloring — ERROR=red, WARN=yellow, INFO=cyan, DEBUG/TRACE=gray, FATAL=bold red
• Resource block suppression — repeated service.name, hostname, etc. blocks shown once, not on every line
• Alt screen bypass — vim, less, top, SSH pass through unmodified
• Level filtering — Show Only ERROR, Show Only WARN+, Show All
• Toggle on/off — flip beautification without closing the terminal
• Set as default — every new terminal beautifies logs automatically

Usage

Option 1: Every new terminal beautifies logs (recommended)

1. Open Command Palette (Cmd+Shift+P / Ctrl+Shift+P)
2. Run OTel: Set as Default Terminal
3. Open any new terminal (`Ctrl+``) — JSON logs are automatically formatted

To revert: Command Palette → OTel: Restore Default Terminal.

Option 2: One-off beautified terminal

1. Open Command Palette
2. Run OTel: Open Beautified Terminal
3. Run your service — JSON log lines are automatically formatted

Commands

Supported log formats

Links

• Source: https://github.com/Trimud/otel-log-beautifier
• Issues: https://github.com/Trimud/otel-log-beautifier/issues
• Changelog: https://github.com/Trimud/otel-log-beautifier/releases