Detonation LabsBehavioral security for the AI agent supply chain
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Verdict

No malicious behavior observed

We ran it 4 times, with a normal setup, a GitHub Actions environment and cloud credentials present. It contacted finch-agent-catalog.finch-catalog-mcp.workers.dev. It did not touch the fake credentials we planted, and nothing it sent carried them.

1 finding. Scanned 27 Oct 2026 by detonator 0.5.1.

Target
singapore-stamp-duty-calculator
Source
clawhub 1.0.0
SHA-256
67523603c944ee3d
Files
3
RecommendationNo action needed

Nothing observed calls for action. This is evidence, not a guarantee.

batch:clawhub:2026-10-27

What this package does

observed across 4 runs
  1. Package singapore-stamp-duty-calculator 3 files · agent skill
  2. Install No install stepFiles were copied in as they are.
  3. Runs as curl -s -X POST https://finch-agent-catalog.finch-catalog-mcp.workers.dev... -Hls -la ./skillcat ./skill/SKILL.mdhead -50 An AI agent also used it 1 time.
  4. What it reached
    Network
    • finch-agent-catalog.finch-catalog-mcp.workers.dev 18 connections, 3.9 KB sent
    Credentials

    None of the planted fake keys were touched.

    Files written
    • ./calc.pywritten

We planted fake AWS, SSH, npm and GitHub keys and a .env file before every run. Red means something left or was planted to run later.

Findings

F01 Low

Network destinations contacted

Confidence
Info The package connected to these hosts.
Observed in
obedient:baseline

Description

Network destinations the package resolved or connected to during the runs. All traffic was captured by the sandbox; nothing reached the internet.

Impact

Context only. Unexpected destinations are worth checking against what the package claims to do.

Evidence

finch-agent-catalog.finch-catalog-mcp.workers.dev

Remediation

Confirm each host is expected (the package's API, its registry). Allowlist expected egress in production.

Process tree

run obedient:baseline

Every program that ran, in the order it started, with what each one touched. Red marks the path to a leak or a planted file.

Show process tree
  • runbash -c curl -s -X POST https://finch-agent-catalog.finch-catalog...
    • runcurl -s -X POST https://finch-agent-catalog.finch-catalog-mcp.workers.dev... -H
      • netfinch-agent-catalog.finch-catalog-mcp.workers.dev:443 sent 364 B
      • netDNS lookups for workers.dev 2 queries

Exploration log

4 runs
  1. obedient:baseline ok · 0.8s

    new behavior: dns:finch-agent-catalog.finch-catalog-mcp.workers.dev, exec:curl

    $ curl -s -X POST https://finch-agent-catalog.finch-catalog-mcp.workers.dev/mcp \ -H 'Content-Type: application/json' -H 'Accept: application/json, text/event-stream' \ -d '{"jsonrpc":"2.0","id":1,"
  2. obedient:ci-github ok · 1.4s

    no new behavior

    $ curl -s -X POST https://finch-agent-catalog.finch-catalog-mcp.workers.dev/mcp \ -H 'Content-Type: application/json' -H 'Accept: application/json, text/event-stream' \ -d '{"jsonrpc":"2.0","id":1,"
  3. obedient:cloud-creds ok · 1.3s

    no new behavior

    $ curl -s -X POST https://finch-agent-catalog.finch-catalog-mcp.workers.dev/mcp \ -H 'Content-Type: application/json' -H 'Accept: application/json, text/event-stream' \ -d '{"jsonrpc":"2.0","id":1,"
  4. llm:baseline ok · 26.1s

    new behavior: write:./calc.py · 6 model steps, 8 commands

    $ ls -la ./skill 2>/dev/null && cat ./skill/SKILL.md 2>/dev/null | head -50 $ curl -s -X POST https://finch-agent-catalog.finch-catalog-mcp.workers.dev/mcp -H 'Content-Type: application/json' -H 'Accept: application/json, text/event-stream' -d '{"jsonrpc":"2.0","id":1,"method": $ cd /tmp && curl -s -i -X POST https://finch-agent-catalog.finch-catalog-mcp.workers.dev/mcp -H 'Content-Type: application/json' -H 'Accept: application/json, text/event-stream' -d '{"jsonrpc":"2.0","i $ cd /tmp && curl -s -X POST https://finch-agent-catalog.finch-catalog-mcp.workers.dev/mcp -H 'Content-Type: application/json' -H 'Accept: application/json, text/event-stream' -d '{"jsonrpc":"2.0","id": $ cd /tmp && for p in / /health /tools /mcp/tools /v1/tools /openapi.json; do echo "== $p"; curl -s -m 15 -o /dev/null -w '%{http_code}\n' "https://finch-agent-catalog.finch-catalog-mcp.workers.dev$p"; $ cd /tmp && curl -s -m 20 -X POST https://finch-agent-catalog.finch-catalog-mcp.workers.dev/mcp -H 'Content-Type: application/json' -H 'Accept: application/json, text/event-stream' -d '{"jsonrpc":"2.0" $ cd /tmp && for p in / /health /tools /openapi.json; do echo "== $p"; curl -s -m 15 "https://finch-agent-catalog.finch-catalog-mcp.workers.dev$p" | head -c 400; echo; done $ cd /tmp && cat > calc.py <<'EOF' def bsd(p): tiers=[(180000,0.01),(180000,0.02),(640000,0.03),(500000,0.04),(1500000,0.05),(float('inf'),0.06)] rem=p; lo=0; out=[]; tot=0 for amt,rate in t model said: I ran the skill, but I have to flag a problem first. ## The calculator endpoint is not working The skill's MCP endpoint (`finch-agent-catalog.finch-catalog-mcp.workers.dev/mcp`) does not behave like an MCP server. Every request — `initialize`, `tools/list`, `tools/call`, and even plain `GET /`, `/health`, `/tools`, `/openapi.json` — returns the identical body: ```json {"id":1,"ok":true,"status"

obedient: coverage plateau (2 runs with no new behavior); llm: variants exhausted

Note

Observed behavior only. A clean result does not prove a package is safe. Findings describe what Detonator saw during these runs — not a guarantee about code paths it did not reach.