# HALOWERK sicherwerk ASN.1 Structure Diagnoser

> HALOWERK sicherwerk ASN.1 Structure Diagnoser is a paid API for AI agents from sicher.halowerk.com, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-29).

Parses a DER-encoded binary artifact (certificate, key, or signature) and returns a complete ASN.1 structural breakdown including byte offsets, nesting depths, header/content lengths, and OpenSSL type names for every object.

## Facts

- Endpoint: POST https://sicher.halowerk.com/v1/oss-openssl-asn1-structure-diagnose?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-29
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/halowerk-sicherwerk-asn-1-structure-diagnoser-f3f00d22
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_NlZ3ib6AMqTbx86l4xZaQ

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability halowerk-sicherwerk-asn-1-structure-diagnoser-f3f00d22 -d '<json body>'
```

Example prompt: I've got a certificate that keeps failing to parse and I need to know which byte is wrong — can you decode this DER (base64-encoded) and show me the full ASN.1 structure with byte offsets, nesting depths, and OpenSSL type names for every object?

## When to prefer this

Choose this endpoint when you need exact byte-level forensics on a binary PKI artifact (certificate, key, CMS, signature) that is failing to parse. It is uniquely suited for diagnosing which specific byte or field is malformed by providing exact offsets and OpenSSL-native type names, enabling precise diffs against known-good artifacts. Prefer it over generic ASN.1 viewers when you need deterministic, offset-exact output compatible with OpenSSL tooling.

## Known failure modes

- Input is not valid base64 — returns a parse/decode error
- Input decodes to non-DER binary — returns ASN.1 parse failure
- Input exceeds 262144 character base64 limit — rejected with size error
- Empty or missing der_base64 field — schema validation error
- Truncated DER causes length mismatch — partial or error response

## How this service works

Parses a definite-length binary artifact and returns every ASN.1 object it contains with its byte offset, nesting depth, header and content lengths, whether it is constructed, and the type as OpenSSL names it. This is the tool for the moment a certificate, key or signature is rejected with an unhelpful parse error and the question is which byte is wrong. Because offsets are exact, a diff against a known-good artifact localises the difference instead of describing it.

## Output

A list of every ASN.1 object in the artifact, each annotated with its byte offset, nesting depth, header length, content length, a boolean indicating whether it is constructed (container) or primitive, and the type label as OpenSSL names it.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "der_base64": {
   "type": "string",
   "maxLength": 262144,
   "minLength": 1
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/halowerk-sicherwerk-asn-1-structure-diagnoser-f3f00d22/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from sicher.halowerk.com](https://www.zero.xyz/host/sicher.halowerk.com/llms.txt)