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.
npx agentmods add skills/dalmasonto/umbral/gitnexus-debuggingnpx skills add dalmasonto/umbral --skill gitnexus-debugginggit clone --depth 1 https://github.com/dalmasonto/umbralWhat 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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5 | $0.00046 | $0.00757 |
| Opus 5 | $0.00023 | $0.00378 |
| Sonnet 5 | $0.00009 | $0.00151 |
| Haiku 4.5 | $0.00005 | $0.00076 |
Grade A, and why
gitnexus-debugging 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 2d ago.
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.
This is a copy
81% identical to gitnexus-debugging — 42 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.
How it starts
The opening of the file, as written. The whole thing — 90 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Debugging with GitNexus
When to Use
- "Why is this function failing?"
- "Trace where this error comes from"
- "Who calls this method?"
- "This endpoint returns 500"
- Investigating bugs, errors, or unexpected behavior
Workflow
1. gitnexus_query({query: "<error or symptom>"}) → Find related execution flows
2. gitnexus_context({name: "<suspect>"}) → See callers/callees/processes
3. READ gitnexus://repo/{name}/process/{name} → Trace execution flow
4. gitnexus_cypher({query: "MATCH path..."}) → Custom traces if needed
If "Index is stale" → run
npx gitnexus analyzein terminal.
Checklist
- [ ] Understand the symptom (error message, unexpected behavior)
- [ ] gitnexus_query for error text or related code
- [ ] Identify the suspect function from returned processes
- [ ] gitnexus_context to see callers and callees
- [ ] Trace execution flow via process resource if applicable
- [ ] gitnexus_cypher for custom call chain traces if needed
- [ ] Read source files to confirm root cause
Debugging Patterns
| Symptom | GitNexus Approach |
|---|---|
| Error message | gitnexus_query for error text → context on throw sites |
| Wrong return value | context on the function → trace callees for data flow |
| Intermittent failure | context → look for external calls, async deps |
| Performance issue | context → find symbols with many callers (hot paths) |
| Recent regression | detect_changes to see what your changes affect |
Tools
gitnexus_query — find code related to error:
gitnexus_query({query: "payment validation error"})
→ Processes: CheckoutFlow, ErrorHandling
→ Symbols: validatePayment, handlePaymentError, PaymentException
gitnexus_context — full context for a suspect:
gitnexus_context({name: "validatePayment"})
→ Incoming calls: processCheckout, webhookHandler
→ Outgoing calls: verifyCard, fetchRates (external API!)
→ Processes: CheckoutFlow (step 3/7)
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.
- 2d ago First seen · 90 lines · 46 tokens per session scan A 4a1e82aa835c
gitnexus-debugging is a skill published in the GitHub repository dalmasonto/umbral (11 stars, last pushed 15d ago), licensed Apache-2.0. It adds 46 tokens to every session and 757 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 0 findings. It is 81% identical to gitnexus-debugging, differing in 42 lines, and is treated as a copy.
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