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 google-calendargit 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/google-calendar)<a href="https://agentmods.dev/skills/vellum-ai/vellum-assistant/google-calendar"><img src="https://agentmods.dev/badge/skills/vellum-ai/vellum-assistant/google-calendar/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/google-calendar"><img src="https://agentmods.dev/badge/skills/vellum-ai/vellum-assistant/google-calendar.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector pass
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 | $0.00019 | $0.01417 |
| Opus 5 | $0.00010 | $0.00709 |
| Sonnet 5 | $0.00004 | $0.00283 |
| Haiku 4.5 | $0.00002 | $0.00142 |
Grade A, and why
google-calendar 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 7d 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.
3. **Never try alternative approaches.** Don't use curl, browser automation, or any workaround. If the scripts can't do it, the reconnection flow is the answer. How it starts
The opening of the file, as written. The whole thing — 94 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Script Reference
All operations use a single CLI script that returns JSON:
- Success:
{ "ok": true, "data": ... } - Failure:
{ "ok": false, "error": "..." }
| Script | Subcommand | Description |
|---|---|---|
scripts/gcal.ts |
list |
List events within a date range |
scripts/gcal.ts |
get |
Get full details of a specific event |
scripts/gcal.ts |
create |
Create a new event (requires user confirmation) |
scripts/gcal.ts |
availability |
Check free/busy times across calendars |
scripts/gcal.ts |
rsvp |
Respond to an event invitation (accepted, declined, tentative) |
Usage Examples
# List events in a date range
bun scripts/gcal.ts list --time-min "2024-01-15T00:00:00Z" --time-max "2024-01-22T00:00:00Z"
# Get full details of a specific event
bun scripts/gcal.ts get --event-id "abc123"
# Create a new event (gates on assistant ui confirm)
bun scripts/gcal.ts create --summary "Team Meeting" --start "2024-01-15T09:00:00-05:00" --end "2024-01-15T10:00:00-05:00" --timezone "America/New_York"
# Check availability for a day
bun scripts/gcal.ts availability --time-min "2024-01-15T00:00:00Z" --time-max "2024-01-15T23:59:59Z"
# RSVP to an event invitation
bun scripts/gcal.ts rsvp --event-id "abc123" --response accepted
# Target a specific connected account (see "Multiple Accounts" below)
bun scripts/gcal.ts list --time-min "2024-01-15T00:00:00Z" --time-max "2024-01-22T00:00:00Z" --account "[email protected]"
Every subcommand accepts --account <email> to select which connected Google account the request runs against. When omitted, the request runs against a single account chosen automatically — safe only when exactly one Google account is connected. Each JSON envelope echoes the queried account in an account field when it is reported by the OAuth layer, so an empty result is self-describing (e.g. No events found in the specified time range for [email protected].).
What ships with it
5 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.
- 7d ago Changed · -7 lines fbfd3eac4931
- 11d ago First seen · 101 lines · 19 tokens per session scan A 22b7784b67e5
google-calendar is a skill published in the GitHub repository vellum-ai/vellum-assistant (1,225 stars, last pushed yesterday), licensed MIT. It adds 19 tokens to every session and 1,417 once invoked, about $0.0001 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 2026-08-30.
Other skills, from other repositories
meeting-notes
Use when the user asks to capture, structure, or summarize meeting notes / call notes / 1:1 discussion / standup notes. Produces a standard template with attendees, agenda, decisions, action items (owner + deadline), and open questions.
skill-factory
A workflow that examines completed session work and turns reusable patterns into Claude Code skills.
ha-settings
Manage Hope Agent application settings through conversation. Use when the user wants to view or change any app configuration: theme, language, enhanced focus indicators, proxy, temperature, notifications, tool timeout, context compaction, automatic session titles, web search, GitHub issue reporting, memory, embedding…
meeting-scheduler
Schedule a small meeting end-to-end: resolve attendee emails, check the owner's calendar for the slot, dedup-check, then create + email the Google Calendar invite. The mechanical core only — cross-person availability negotiation stays interactive.
relay
Write a handoff/continuity note for the NEXT Sutando session. Captures what was just in flight, what to check first, what might go wrong, and implicit context the structured snapshot doesn't carry. Drained into session-state.md by src/session-handoff.sh.
x-twitter
Post to X via a signed-in browser session (live method — no API keys); API v2 path for search/read/engagement.