# Runtime Binding Verification

> Prove how an abstraction, interface, mode, or configured choice becomes the concrete runtime implementation actually used, including DI/bootstrap/factory/provider/registry and alternate branches.

- Skill: `tuana-vn/runtime-binding-verification` (Agent Skill)
- Install (CLI): `npx skillmds@latest add tuana-vn/runtime-binding-verification`
- Raw SKILL.md: https://api.skillmd.com/api/skills/tuana-vn/runtime-binding-verification/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Coding & Dev Tools
- Author: tuana-vn (https://skillmd.com/u/tuana-vn)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/tuana-vn/runtime-binding-verification

---


# Runtime Binding Verification

## Mission

Close the gap between:

```text
"an implementation exists"
```

and:

```text
"this implementation is actually selected under these runtime conditions"
```

## Start From

One high-impact abstraction, selector, factory, client, repository, handler, or mode whose active implementation matters.

## Trace

Trace both directions where needed:

```text
startup/bootstrap
→ registration / DI / provider / registry
→ selector/factory
→ config/runtime state
→ concrete implementation
→ real caller/use
```

and:

```text
runtime caller
→ abstraction
→ creation/lookup
→ concrete instance
→ boundary
```

## Search

Inspect as applicable:

- constructors and `new`
- dependency injection annotations/config
- service loaders/plugins
- factories/providers/builders
- registries/maps
- startup/main/application initialization
- reflection/class-name loading
- configuration mode switches
- test-only bindings vs production bindings
- legacy/inactive implementations
- fallback implementations

## Counterexample Search

Search for every implementation and every creation/registration path of the abstraction.

Do not conclude from one call site.

## Output

Create/update:

```text
docs/reverse-engineering/runtime-binding/<scope>.md
```

Required table:

| Scope/Condition | Abstraction | Binding Mechanism | Concrete Implementation | Config/Runtime Input | Active Evidence | Alternate Binding | Verdict |
|---|---|---|---|---|---|---|---|

Verdict:

```text
VERIFIED_ACTIVE
VERIFIED_ALTERNATE
INACTIVE_LEGACY
TEST_ONLY
UNRESOLVED
```

Promote only after counterexample search and scope check.