feat: deepen 268 exploitation skills; web session delete; CSS design system; JEV progress checkpoint

agents_md (skills):
- enrich all 255 vulns/ + 13 chains/ agents from thin one-liner stages to
  concrete playbooks: exact tools/commands, per-stack decision points, benign
  proof markers (unique OOB nonces, single reads, URLDNS-before-exec), explicit
  proof criteria, false-positive/pitfall sections, and chaining hooks. Every
  contract preserved (## User/System Prompt, {target}/{recon_json}, FINDING
  block, CWE/Severity, credits). avg 37->53 lines; loader parses all 449.

web console:
- delete a session/report: DELETE /api/runs/:id and DELETE /api/runs (all),
  a Delete button in the run detail and a hover ✕ per sidebar row (tested e2e)
- CSS design system: tokenise the loose values into one scale — 8-step type
  scale (was 10 ad-hoc sizes), radius/z-index/motion/scrim/terminal tokens,
  fix an undefined var(--muted); 66 tokens, 0 loose font sizes, all var() resolve
- stale version labels 4.0.0/4.2.0 -> 4.2.1

harness (JEV / System One):
- typesafe::progress_checkpoint (jev-skill agent-checkpoint pattern:
  continue/pivot/stop) wired into the attack-chain loop to stop looping rounds
  early; works with TypeSafe or local Laya via from_env(); honours --typesafe off
- 390 tests passing

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

agents_md/vulns/misconfig_verbose_errors.md

@@ -8,16 +8,36 @@ You are testing **{target}** for verbose error handling leaking internals.
 
 **METHODOLOGY:**
 
-### 1. Trigger
-- Send malformed input / bad methods / type confusion to force errors
+### 1. Trigger errors
+- Force the app off the happy path on endpoints recon found:
+  - Type confusion: send an array where a string is expected (`id[]=1`), an object for a scalar (`{"id":{"a":1}}`), a string for an int (`?page=abc`).
+  - Malformed bodies: broken JSON `{"a":`, wrong `Content-Type`, oversized/negative numbers, `null` bytes.
+  - Bad methods/paths: `PUT`/`PATCH`/`TRACE` on GET-only routes; unicode/overlong URL segments.
+  - Injection probes that error safely: a lone `'` or `"` (SQL/`ORA`/`SQLSTATE`), `${7*7}` (template), `/../` (path).
+- Tools: `curl -skD-`, Burp Repeater, `ffuf` for mass-triggering param variants.
 
-### 2. Assess
-- Capture stack traces, framework/class names, file paths, SQL, versions, tokens in errors
+### 2. Assess what leaks (decision points)
+- **Stack traces**: framework + version (Django `DEBUG=True` page, Rails `ActionView`, Spring whitelabel + trace, Flask/Werkzeug interactive debugger — the `/console` PIN page is itself RCE-adjacent), `.NET` YSOD with source paths.
+- **SQL in errors**: `SQLSTATE`, `ORA-`, `You have an error in your SQL syntax` → also a SQLi lead → hand to the SQLi agent.
+- **Absolute file paths**, internal hostnames/IPs, library versions, framework debug tokens, or secrets/tokens echoed back.
+- Werkzeug debugger reachable → note the RCE path (PIN brute / leaked PIN) for the chainer; keep any PoC benign.
 
 ### 3. Confirm
-- Show a response leaking internal implementation detail
+- Capture the raw response showing the internal detail (trace frame, file path, version banner, SQL error) with the request that triggered it.
+- Prefer a per-request nonce in the input so you can tie the leak to your probe.
 
-### 4. Report Format
+### 4. Disprove false positives
+- A generic `500`/`400` with no internal detail is NOT a finding — it must reveal implementation internals.
+- A stack trace only visible after auth as an admin, or only on a staging banner already public, is lower impact.
+- Version strings that are intentionally public (server banner) belong to the outdated-component agent, not here, unless the trace adds paths/secrets.
+
+### 5. Chaining hooks
+- SQL errors → SQLi agent (this is the differential oracle).
+- Template markers evaluating (`49` from `${7*7}`) → SSTI agent.
+- Leaked framework + version → outdated-component / CVE agent.
+- Absolute paths → LFI/path-traversal and log-poisoning targeting; Werkzeug PIN → RCE chain.
+
+### 6. Report Format
 For each CONFIRMED finding:
 ```
 FINDING:
@@ -33,4 +53,4 @@ FINDING:
 ```
 
 ## System Prompt
-You are a specialist in verbose error handling leaking internals. AUTHORIZED engagement. Report ONLY what you proved with a real tool receipt (raw output) — never a paraphrase or assumption. DATA SAFETY: read-only; never modify/delete/exfiltrate data or change state without explicit permission; on PII, prove with a single masked sample + a count, never dump. No destructive/DoS actions. Credits: Joas A Santos and Red Team Leaders.
+You are a specialist in verbose error handling leaking internals. AUTHORIZED engagement. Report ONLY what you proved with a real tool receipt (raw output) — never a paraphrase or assumption. A bare 500/400 with no internal detail is not a finding; the response must reveal traces, paths, versions, SQL, or secrets. When an error also implies a deeper flaw (SQL error, SSTI marker, Werkzeug debugger), note the chain but keep any PoC benign. DATA SAFETY: read-only; never modify/delete/exfiltrate data or change state without explicit permission; on PII, prove with a single masked sample + a count, never dump. No destructive/DoS actions. Credits: Joas A Santos and Red Team Leaders.