Vellum Assistant is a personal AI assistant that remembers information about users, learns their preferences, and takes actions across connected apps. It is intended for people who want an assistant that can manage conversations, unfinished work, and proactive notifications over time. The catalogue skills, hooks, instruction, and setting configure or extend how the assistant works.
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 vellum-ai/vellum-assistant --skill slack-app-setupgit clone --depth 1 https://github.com/vellum-ai/vellum-assistantWrote 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/vellum-ai/vellum-assistant/slack-app-setup)<a href="https://agentmods.dev/skills/vellum-ai/vellum-assistant/slack-app-setup"><img src="https://agentmods.dev/badge/skills/vellum-ai/vellum-assistant/slack-app-setup/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/vellum-ai/vellum-assistant/slack-app-setup"><img src="https://agentmods.dev/badge/skills/vellum-ai/vellum-assistant/slack-app-setup.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector warn
SkillSpector: 3 findings, 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 Excessive Agency · line 57 Skill enables autonomous high-impact decisions without human-in-the-loop verification. Critical operations (destructive commands, financial transactions, data deletion) should require explicit user confirmation.Fix: Add human-in-the-loop confirmation for destructive, irreversible, or high-impact operations. Never auto-execute commands that modify files, send data, or alter system state.
- medium Data Exfiltration · line 136 Data is being sent to an external URL. This could be legitimate telemetry or data exfiltration. Manual review is recommended.Fix: Verify the destination URL is trusted and necessary. Remove or replace with documented APIs. Ensure no secrets, tokens, or PII are transmitted.
- medium Data Exfiltration · line 147 Data is being sent to an external URL. This could be legitimate telemetry or data exfiltration. Manual review is recommended.Fix: Verify the destination URL is trusted and necessary. Remove or replace with documented APIs. Ensure no secrets, tokens, or PII are transmitted.
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 | $0.00071 | $0.02299 |
| Opus 5 | $0.00036 | $0.01149 |
| Sonnet 5 | $0.00014 | $0.00460 |
| Haiku 4.5 | $0.00007 | $0.00230 |
Grade A, and why
slack-app-setup scanned grade A with 1 finding 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 8d 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.
Makes network callslowCapability
Not a fault in itself. Listed so you know the mod talks to something, and to what.
command: "curl -s -X POST https://slack.com/api/auth.test" How it starts
The opening of the file, as written. The whole thing — 156 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Scope
This skill connects an assistant to a Slack workspace: first-time bot identity (tokens, scopes, events), or switching workspaces and rotating tokens. Runtime Slack operations (posting, reading channels, triage) belong to the separate slack skill.
Step 1 — Check existing configuration
Run assistant credentials list --search slack_channel (via the bash tool). Scan the result for entries with service: slack_channel and note which of app_token, bot_token are present.
Then branch:
- If both ✅ → fully configured. Offer to show status or reconfigure. Stop here unless the user wants a reset.
- Otherwise → continue to Step 2.
✓ Checkpoint: You named which of
app_token/bot_tokenare present before branching. Do not skip theassistant credentials listcall and guess.
Step 2 — Open the setup wizard
Call ui_show with surface_type: "channel_setup" and data: { channel: "slack" }. This opens the Slack setup wizard in the side panel. The wizard is non-blocking — the tool returns immediately.
⚠️ CRITICAL: Tool call first, announcement second — in the same turn. Do not write any message that says the wizard is open (or is opening) until the ui_show call has returned success earlier in the same turn. A message claiming the wizard is open when the tool was never called shows the user an empty side panel.
After ui_show returns success, tell the user:
I've opened the Slack setup wizard in the side panel. It will walk you through creating a Slack app from a manifest and connecting it — complete the steps there. The wizard will auto-notify me when you close it. If you run into issues along the way, ask me in chat.
Hand-off notification (phones and narrow windows). On phone-sized clients the setup opens on the Contacts page instead of a side drawer, and completing it there cannot auto-notify. The client signals this with a hidden message like [User action on channel_setup surface: moved the slack setup to the Contacts page]. When you receive that hand-off notification, tell the user:
What ships with it
1 file 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.
- 8d ago Changed · -6 lines 991e4da25f4d
- 9d ago First seen · 162 lines · 71 tokens per session scan A 35d7e92d4ee2
slack-app-setup is a skill published in the GitHub repository vellum-ai/vellum-assistant (1,234 stars, last pushed today), licensed MIT. It adds 71 tokens to every session and 2,299 once invoked, about $0.0004 per session on Opus 5. A static security scan graded it A with 1 finding (makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-09-03.
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Takes any security finding, error message, or jargon-heavy security advice and explains it in plain English. Use this when someone is confused by what /lictor-security-check found, or when they got a security warning from another tool and don't understand it.
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