explain

A command for explaining why a software package appears in a project's dependency list. A dependency is a library that another package or the project needs to run or build.

In plain words
What is it for?
Use it to trace packages in supported ecosystems, including packages brought in by other libraries. It can inspect local projects and other targets using the same target options as dependency scanning.
Why use it?
It shows every path by which the named package enters the project, including indirect dependencies. This makes it easier to understand whether a package can be upgraded, removed, or has multiple sources.

Command

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 commands/bomly-dev/bomly-cli/explain
Clone the repo
git clone --depth 1 https://github.com/bomly-dev/bomly-cli
Per session 0 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 567 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 $0.00000 $0.00567
Opus 5 $0.00000 $0.00283
Sonnet 5 $0.00000 $0.00113
Haiku 4.5 $0.00000 $0.00057

Measured yesterday against content hash c25554d545fc, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

explain 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.

docs/commands/explain.md · 62 lines

How it starts

The opening of the file, as written. The whole thing — 62 lines — stays where its author put it; the contents beside it link to each section on GitHub.

bomly explain

Answer "why is this package here?" — trace every dependency path that pulls a package into the graph. explain runs the same detect and match stages as scan, then walks the graph from the project roots to the package you named.

Minimal invocation

bomly explain send

On a project that depends on express:

ecosystem  npm
manager    npm
package    [email protected]
scope      runtime
direct     no
licenses
  MIT [declared]
introduced by:
  [email protected]
  └─ [email protected]
     ├─ [email protected] [analyzed] (transitive)
     └─ [email protected]
        └─ [email protected] [analyzed] (transitive)

Every path is shown, not just the shortest one — here send enters both directly through express and again through serve-static, which matters when you're deciding what to bump.

Naming the package

Pass a package name or a full PURL. A PURL disambiguates when the same name exists in more than one ecosystem:

bomly explain lodash
bomly explain pkg:npm/react
bomly explain github.com/spf13/cobra --path ./backend

Targets and gates

explain accepts the same target flags as scan (--path, --recursive, --url/--ref, --image, --sbom) and the same pipeline gates. Add --enrich to include the package's vulnerabilities in the explanation, and --audit/--analyze when you want policy findings or reachability on it:

bomly explain send --enrich            # include known vulnerabilities
bomly explain send --enrich --analyze  # and whether they're reachable
bomly explain send --json              # structured paths for tooling

The JSON shape is documented in the explain schema.

Exit codes

Same table as every command — see Exit Codes. Notably 5 when the target has no supported manifests, and 4 for a malformed PURL.

See also

  • scan — the shared target, gate, and output flags
  • diff — when the question is "what changed" rather than "why is it here"
  • Interactive TUI — explore the same paths interactively with bomly scan --interactive

Read the full file on GitHub · 62 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 · 62 lines · 0 tokens per session scan A c25554d545fc

Subscribe to this mod's changes

explain is a command published in the GitHub repository bomly-dev/bomly-cli (11 stars, last pushed 2d ago), licensed Apache-2.0. It costs nothing until one of its globs matches a file; then it loads 567 tokens. 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.