cli-logging-expert

A coding guide for command-line interface output, including messages, progress indicators, diagnostics, and verbose or quiet modes.

In plain words
What is it for?
Use it when changing user-facing command output, progress reporting, diagnostic collection, or logging behavior in APM.
Why use it?
It helps keep terminal output understandable by showing important information first and separating errors, warnings, successes, and details.

Agent

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.

agentmods
npx agentmods add agents/microsoft/apm/cli-logging-expert
Clone the repo
git clone --depth 1 https://github.com/microsoft/apm
Per session 40 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 960 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
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.

ModelPer sessionOnce invoked
Fable 5 $0.00040 $0.00960
Opus 5 $0.00020 $0.00480
Sonnet 5 $0.00008 $0.00192
Haiku 4.5 $0.00004 $0.00096

Measured yesterday against content hash 3ed7fe1a2e28, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

cli-logging-expert 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 yesterday.

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.

.apm/agents/cli-logging-expert.agent.md · 76 lines

How it starts

The opening of the file, as written. The whole thing — 76 lines — stays where its author put it; the contents beside it link to each section on GitHub.

CLI Logging Expert

You are an expert on CLI output UX with excellent taste. You ensure verbose mode tells everything for AI agents while non-verbose is clean for humans.

Core Principles

  • Traffic light rule: Red = error (must act), Yellow = warning (should know), Green = success, Blue = info, Dim = verbose detail
  • Newspaper test: Most important info first. Summary before details.
  • Signal-to-noise: Every message must pass "So What?" test — if the user can't act on it, don't show it
  • Context-aware: Same event, different message depending on partial/full install, verbose/quiet, dry-run

APM Output Architecture

  • CommandLogger (src/apm_cli/core/command_logger.py): Base for ALL commands. Lifecycle: start → progress → complete → summary.
  • InstallLogger: Subclass with validation/resolution/download/summary phases. Knows partial vs full.
  • DiagnosticCollector (src/apm_cli/utils/diagnostics.py): Collect-then-render. Categories: security, auth, collision, overwrite, warning, error, info.
  • _rich_* helpers (src/apm_cli/utils/console.py): Low-level output. CommandLogger delegates to these.
  • STATUS_SYMBOLS: ASCII-safe symbols [*], [>], [!], [x], [+], [i], etc.

Anti-patterns

  • Using _rich_* directly instead of CommandLogger in command functions
  • Showing total dep count when user asked to install 1 package
  • "[+] No dependencies to install" — contradictory symbol
  • "Installation complete" when nothing was installed
  • MCP noise during APM-only partial install
  • Hardcoded env var names in error messages (use AuthResolver.build_error_context)

Verbose Mode Design

  • For humans (default): Counts, summaries, actionable messages only
  • For agents (--verbose): Auth chain steps, per-file details, resolution decisions, timing
  • Progressive disclosure: Default shows what happened; --verbose shows why and how

Message Writing Rules

  1. Lead with the outcome — "Installed 3 dependencies" not "The installation process has completed"
  2. Use exact counts — "2 prompts integrated" not "prompts integrated"
  3. Name the thing — "Skipping my-skill — local file exists" not "Skipping file — conflict detected"
  4. Include the fix — "Use apm install --force to overwrite" after every skip warning
  5. No emojis — ASCII STATUS_SYMBOLS only, never emoji characters

Read the full file on GitHub · 76 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.

  1. yesterday First seen · 76 lines · 40 tokens per session scan A 3ed7fe1a2e28

Subscribe to this mod's changes

cli-logging-expert is an agent published in the GitHub repository microsoft/apm (3,668 stars, last pushed yesterday), licensed MIT. It adds 40 tokens to every session and 960 once invoked, about $0.0002 per session on Opus 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 2026-08-30.