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 skills add PostHog/posthog-foss --skill authoring-error-tracking-alertsgit clone --depth 1 https://github.com/PostHog/posthog-fossWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/skills/posthog/posthog-foss/authoring-error-tracking-alerts)<a href="https://agentmods.dev/skills/posthog/posthog-foss/authoring-error-tracking-alerts"><img src="https://agentmods.dev/badge/skills/posthog/posthog-foss/authoring-error-tracking-alerts/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/skills/posthog/posthog-foss/authoring-error-tracking-alerts"><img src="https://agentmods.dev/badge/skills/posthog/posthog-foss/authoring-error-tracking-alerts.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector warn
SkillSpector: 1 finding, up to medium
These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →
- medium Prompt Injection · line 50 Large whitespace padding was detected (a block of blank lines or a long run of spaces). This can push injected instructions below or to the right of the visible area so a human reviewer never sees them while the agent still reads them. Manual review of the hidden content is recommended.Fix: Remove the large whitespace padding (blank-line blocks or long space runs) and review any content hidden below or to the right of it. Keep skill files compact and reviewable so no instructions can be
What 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 5.1 | $0.00081 | $0.02122 |
| Opus 5 | $0.00041 | $0.01061 |
| Sonnet 5 | $0.00016 | $0.00424 |
| Haiku 4.5 | $0.00008 | $0.00212 |
Grade A, and why
authoring-error-tracking-alerts 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 6d 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.
Copies of this mod
1 near-identical copy found in the catalogue:
- authoring-error-tracking-alerts — 100% identical, 0 lines differ
How it starts
The opening of the file, as written. The whole thing — 182 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Authoring error tracking alerts
Authoring an error tracking alert is a routing problem, not a measurement problem. The trigger events already exist and fire on real conditions in the ingestion pipeline — your job is to pick the right trigger for the user's intent, dedupe against what's already configured, and wire a destination they can actually act on.
When to use this skill
- The user asks to set up alerts / notifications for errors or exceptions in their project.
- The user wants a starter set of alerts after enabling error tracking.
- The user pastes an issue link and asks "notify me when this happens again" — usually
_reopenedwith a per-issue property filter.
When not to use this skill
- Tuning the spike detector itself (multiplier, window, threshold). That lives behind the spike detection config endpoint and is not exposed via MCP today.
- Investigating an active incident — query the issue / its events directly via
posthog:query-error-tracking-issueandposthog:query-error-tracking-issue-eventsinstead of authoring more alerts mid-fire. - Configuring volume-threshold alerts (count of
$exceptionevents over a window). That's a logs-style alert and is not in scope here — error tracking alerts ride the lifecycle events instead.
Tools
| Tool | Job | Where it fits |
|---|---|---|
posthog:error-tracking-alerts-list |
List existing alerts; dedupe before creating. | Step 2 — dedupe. |
posthog:integrations-list |
Find the user's Slack workspace id (filter by kind=slack). |
Step 3 — pick channel. |
posthog:integrations-channels-retrieve |
List Slack channels for a workspace. | Step 3 — pick channel. |
posthog:error-tracking-alerts-create |
Create the alert (HogFunction with type=internal_destination). |
Step 4 — ship. |
posthog:error-tracking-alerts-partial-update |
Toggle, rename, or modify an existing alert. | When tuning, not authoring. |
posthog:error-tracking-alerts-delete |
Soft-delete an alert. | When the user says "remove". |
What ships with it
2 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
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.
- 6d ago First seen · 182 lines · 81 tokens per session scan A 0e969bc8f472
authoring-error-tracking-alerts is a skill published in the GitHub repository PostHog/posthog-foss (714 stars, last pushed today), licensed MIT. It adds 81 tokens to every session and 2,122 once invoked, about $0.0004 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-09-03.
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