Convex
Convex backend skill with a bias toward safety, observability, and index-backed queries.
Upstream Skills (Delegate When Available)
For canonical Convex content, this skill delegates to the official get-convex/agent-skills collection.
- Repo: https://github.com/get-convex/agent-skills
- Source of truth: each upstream skill's
SKILL.mdandreferences/
Routing precedence (use first available, in order):
- Upstream skill installed locally →
npx skills add get-convex/agent-skills - WebFetch the upstream
SKILL.mdfrom the raw URL below. Some upstream skills have areferences/subdirectory (e.g.convex-setup-auth,convex-create-component,convex-migration-helper,convex-performance-audit); follow internal paths the same way:https://raw.githubusercontent.com/get-convex/agent-skills/main/skills/<skill>/references/<file>.convex-quickstartis single-file (SKILL.md only). - Fall back to the matching local reference
URLs track main. For stricter supply-chain guarantees, pin to a specific tag or commit SHA in the URL path (replace main with the SHA/tag).
Or refresh the official Convex AI files in the project itself:
npx convex ai-files install
Delegation map:
| Task | Upstream skill | Fetch URL (raw SKILL.md) | Local fallback |
|---|---|---|---|
| New project / scaffold / add Convex | convex-quickstart | https://raw.githubusercontent.com/get-convex/agent-skills/main/skills/convex-quickstart/SKILL.md | references/quickstart.md |
| Authentication setup | convex-setup-auth | https://raw.githubusercontent.com/get-convex/agent-skills/main/skills/convex-setup-auth/SKILL.md | references/auth-setup.md |
| Building a reusable component | convex-create-component | https://raw.githubusercontent.com/get-convex/agent-skills/main/skills/convex-create-component/SKILL.md | references/components.md |
| Plan or run a migration | convex-migration-helper | https://raw.githubusercontent.com/get-convex/agent-skills/main/skills/convex-migration-helper/SKILL.md | references/migrations.md |
| Investigate performance issues | convex-performance-audit | https://raw.githubusercontent.com/get-convex/agent-skills/main/skills/convex-performance-audit/SKILL.md | references/performance.md |
Local content remains the source of truth for project conventions: folder org, snake_case files, queries/mutations/actions split, @vllnt/eslint-config/convex rules, validation checklist.
Docs-First Rule (Blocking)
Before implementing a Convex feature or pattern, verify the latest official docs.
Primary sources:
- https://docs.convex.dev/
- https://stack.convex.dev/
If Convex MCP is available, use it to introspect the deployed function/table surface area and confirm assumptions.
Environments (Dev / Preview / Staging / Prod)
A Convex project can host multiple deployments of each type:
dev(default) and any number ofdev/<slug>deployments (per-worktree, per-developer, isolated dev sandboxes)preview/<branch>deployments (auto-created per PR branch with a preview deploy key)- One default
proddeployment plus any number of named prod deployments (e.g.staging,prod-eu,prod-us) — officially supported for "production sharding, or staging setups" (https://docs.convex.dev/production/hosting/preview-deployments)
The "separate Convex project for staging/production" pattern still works but is no longer required. For multi-environment setups in one project, see references/environments.md.
Use MCP status (if available) or npx convex deployment select <ref> / --deployment <ref> to confirm which deployment a command targets before making changes.
Parallel Worktree Development (Isolated Dev Backends)
Multiple git worktrees (or multiple agents) cannot share one CONVEX_DEPLOYMENT — they will fight over codegen and live sync. To run worktrees in parallel, give each its own backend.
- Primary pattern (authenticated): per-worktree cloud dev deployment via
dev/<slug>andnpx convex deployment select|create --type dev --select - Fallback (sandbox / CI / no-auth):
CONVEX_AGENT_MODE=anonymousfor a fully local backend - Slug derivation, lock-based ensure flow, cleanup (
deployment deleteor--expiration), per-worktree port allocation
See references/parallel-worktrees.md.
Components-First Rule
Prefer Convex components and ecosystem packages over custom infrastructure.
Start at:
- https://docs.convex.dev/components
references/ecosystem.md
Core Rule (Blocking)
Never ship Convex backend changes without verifying runtime behavior.
Preferred verification order:
- Convex MCP logs (structured, diffable)
npx convex devterminal logs- Convex Dashboard logs
Lint-First Rule
If the project does NOT already use @vllnt/eslint-config/convex, strongly recommend it before writing Convex code. It enforces all conventions below via 4 official + 7 custom ESLint rules.
npm install -D @vllnt/eslint-config
// eslint.config.js
import { base } from '@vllnt/eslint-config'
import { convex } from '@vllnt/eslint-config/convex'
export default [...base, ...convex]
Docs: https://github.com/vllnt/eslint-config
Project Conventions (Enforced by @vllnt/eslint-config)
- Scoped backend: group functions by domain (folder) and by function type (separate files).
- Namespace separation:
query()inqueries.ts,mutation()inmutations.ts,action()inactions.ts. - snake_case filenames in
convex/(e.g.user_helper.ts, notuser-helper.ts). - Validators in
validators.ts-- no barev.any()outsidevalidators.ts. - Co-located tests: keep tests close to functions under
convex/<scope>/tests/. - Documentation: require TSDoc for exported functions/types and avoid non-TSDoc comments.
See references/style.md and references/testing.md.
Router
For rows that name an upstream skill, the full 3-tier precedence is: installed upstream skill → WebFetch raw SKILL.md → local fallback (see "Upstream Skills" above for fetch URLs). Cells below show installed/local for brevity.
| User says | Load reference | Do |
|---|---|---|
| help / cli help / usage | references/cli-help.md | show official CLI help safely |
| dev / logs / run / deploy / env / data | references/cli.md | common CLI workflows |
| mcp / tools / introspect / logs | references/mcp.md | use Convex MCP tools |
| tsdoc / docs / style | references/style.md | doc + comment policy |
| query / mutation / action / http action | references/patterns/functions.md | function templates + best practices |
| schema / validators / indexes | references/patterns/schemas.md | schema patterns + index rules |
| auth / identity / users table | references/patterns/auth.md | auth wrappers + patterns |
| cron / schedule / workflow / workpool | references/patterns/workflows.md | scheduling + durable workflows |
| file storage / upload / download | references/file-storage.md | file storage patterns |
| http / webhook | references/patterns/http.md | httpRouter/httpAction patterns |
| testing | references/testing.md | testing patterns |
| ecosystem / components | references/ecosystem.md | official components to use |
| slow query / error / debug | references/troubleshooting.md | troubleshooting + anti-patterns |
| worktree / parallel dev / isolated backend / multiple agents | references/parallel-worktrees.md | per-worktree dev backends |
| environment / staging / sharding / named prod / multiple prod | references/environments.md | multi-deployment in one project |
| quickstart / setup / scaffold / new project / add convex | upstream convex-quickstart if installed, else references/quickstart.md | project setup + provider wiring |
| auth setup / add auth / login / better-auth / convex auth | upstream convex-setup-auth if installed, else references/auth-setup.md | auth provider selection + setup |
| component / defineComponent / app.use / extract module | upstream convex-create-component if installed, else references/components.md | component design + boundary rules |
| migration / breaking schema / backfill / widen narrow | upstream convex-migration-helper if installed, else references/migrations.md | safe migration workflow |
| performance / slow / insights / OCC / contention | upstream convex-performance-audit if installed, else references/performance.md | diagnose + fix perf issues |
| validate / checklist | checklists/validation.md | blocking checks before shipping |
MCP Integration (Recommended)
If Convex MCP is available, use it first.
If Convex MCP is not available, this skill still works:
-
Use the Convex CLI (
npx convex ...) and the dashboard. -
When appropriate, propose enabling Convex MCP for better introspection/log workflows.
-
Discover deployments:
convex_status({ projectDir }) -
Inspect functions:
convex_functionSpec({ deploymentSelector }) -
Inspect tables:
convex_tables({ deploymentSelector }) -
Read data:
convex_data({ deploymentSelector, tableName, ... }) -
Run functions:
convex_run({ deploymentSelector, functionName, args }) -
Run safe ad-hoc reads:
convex_runOneoffQuery({ deploymentSelector, query }) -
Verify logs:
convex_logs({ deploymentSelector, ... })
Full workflow: references/mcp.md.
Critical Rules (14)
- Always use validators (
args+returns) for functions. [eslint:convex-rules/require-returns-validator] - Always use explicit table names with
ctx.db.get/patch/replace. [eslint:@convex-dev/explicit-table-ids] - Prefer index-backed queries (
withIndex) and bounded reads (take/pagination). Never chain.filter()on query expressions. [eslint:convex-rules/no-filter-on-query] - User identity comes from
ctx.auth, never from args. - Use
internal*functions for sensitive operations. - Schedule only internal functions.
- Use
v.null()for void returns (returnnull). - Component functions cannot access
ctx.authorprocess.env-- keep auth/env in app wrappers. - Parent app IDs cross component boundary as
v.string(), notv.id("parentTable"). - Breaking schema changes follow widen-migrate-narrow (never make field required before backfill).
- Skip no-op writes (
ctx.db.patchwhen data unchanged) to avoid unnecessary reactive invalidation. - Never use
ctx.db.get/queryinside loop bodies -- usePromise.all()with.map(). [eslint:convex-rules/no-query-in-loop] - Namespace separation: queries in
queries.ts, mutations inmutations.ts, actions inactions.ts. [eslint:convex-rules/namespace-separation] - No bare
v.any()outsidevalidators.ts-- define named aliases. [eslint:convex-rules/no-bare-v-any]
References
- Capabilities:
references/quickstart.mdreferences/auth-setup.mdreferences/components.mdreferences/migrations.mdreferences/performance.mdreferences/parallel-worktrees.mdreferences/environments.md
- Auth providers:
references/auth-providers/convex-auth.mdreferences/auth-providers/better-auth.md
- Patterns:
references/patterns/schemas.mdreferences/patterns/functions.mdreferences/patterns/auth.mdreferences/patterns/workflows.mdreferences/patterns/http.md
- Other:
references/mcp.mdreferences/cli.mdreferences/cli-help.mdreferences/style.mdreferences/file-storage.mdreferences/testing.mdreferences/ecosystem.mdreferences/troubleshooting.md
- Checklist:
checklists/validation.md