Nika ships with 105 MCP server entries in its catalog, aligned with
the official MCP Registry schema
(v2025-12-11). Each entry declares one or more local-install
packages (npm / pypi / oci / cargo / mcpb) and/or remotes
(streamable-http / sse endpoints). The workflow YAML invoke: verb
references servers by id — Nika handles the rest.
Canonical source: crates/nika-catalog/data/mcp-servers.tomlnika/mcp-servers@1.0. Snapshot 2026-04-17 — grep -c '^\[\[servers\]\]'
= 105 . Build-time invariants (enforced in build.rs): unique ids,
packages+remotes non-empty, known category, pricing ∈ , alias non-collision.Overview
Categories 17 — from anthropic to vectordb
Invocation invoke: verb with server: <id>
How to invoke one workflow.nika.yaml
Required env
nika : v1 workflow : scrape-and-summarise tasks : - id : crawl invoke : tool : "mcp:firecrawl/scrape" # mcp:<server>/<tool> · server id from the catalog below args : url : https://example.com - id : summarise depends_on : [ crawl ] infer : model : anthropic/claude-sonnet-4-6 # <provider>/<name> prompt : "Summarise: ${{ tasks.crawl.output.content }}"
Verb invoke: is live in v. The Nika MCP catalog here is
about workflows calling external MCP tools; Nika’s own agent-facing MCP
server remains read-only (nika_check, nika_explain).
By category Shipped by the Model Context Protocol project itself. Id Title Registry Identifier filesystemFilesystem npm @modelcontextprotocol/server-filesystemmemoryMemory npm @modelcontextprotocol/server-memorypdfPDF npm @modelcontextprotocol/server-pdf
One-liners:
filesystem — read and write local files with path-based access control.memory — persistent key/value memory store.pdf — PDF text + structure extraction. Build systems, browser automation, error trackers, CI / CD. Id Title Registry Identifier awsAWS npm aws-mcpbitbucketBitbucket npm @nexus2520/bitbucket-mcp-serverbrowserbaseBrowserbase npm @browserbasehq/mcpbrowserstackBrowserStack npm @browserstack/mcp-serverchrome-devtoolsChrome DevTools npm chrome-devtools-mcpcircleciCircleCI npm @circleci/mcp-server-circlecicloudflareCloudflare npm @cloudflare/mcp-server-cloudflareeslintESLint npm @eslint/mcpfigmaFigma npm figma-developer-mcplaunchdarklyLaunchDarkly npm @launchdarkly/mcp-serverlinearLinear npm mcp-server-linearnxNx npm nx-mcpplaywrightPlaywright (browser automation) npm @playwright/mcppostmanPostman npm @postman/postman-mcp-serversentrySentry npm @sentry/mcp-serververcelVercel npm vercel-mcpxcodeXcode (build + simulator) npm xcodebuildmcp
Calendars, project trackers, note-taking, knowledge bases. Id Title Registry Identifier airtableAirtable npm airtable-mcp-serverclickupClickUp npm @taazkareem/clickup-mcp-serverexcelExcel npm @negokaz/excel-mcp-servergoogle-calendarGoogle Calendar npm @cocal/google-calendar-mcpgoogle-driveGoogle Drive npm @modelcontextprotocol/server-gdrivejiraJira npm jira-mcpmondayMonday npm @mondaydotcomorg/monday-api-mcpn8nn8n npm n8n-mcpnotionNotion npm @notionhq/notion-mcp-serverobsidianObsidian (vault access) npm obsidian-mcpslackSlack npm @modelcontextprotocol/server-slackzendeskZendesk npm zendesk-mcp
Embeddings, agents, sandboxes, documentation lookup. Id Title Registry Identifier 21st21st.dev Magic npm @21st-dev/magicahrefsAhrefs npm @ahrefs/mcpcontext7Context7 npm @upstash/context7-mcpdataforseoDataForSEO npm dataforseo-mcp-servere2bE2B npm @e2b/mcp-serverlangchainLangchain npm langchain-mcpsequential-thinkingSequential Thinking npm @modelcontextprotocol/server-sequential-thinkingsupadataSupadata npm @supadata/mcp
Scrapers, search APIs, crawlers. Id Title Registry Identifier apifyApify npm @apify/actors-mcp-serverexaExa npm exa-mcp-serverfirecrawlFirecrawl (scrape + crawl) npm firecrawl-mcpperplexityPerplexity (search + sonar) npm perplexity-mcpsearchapiSearchapi npm searchapi-mcpserperSerper npm mcp-server-serpertavilyTavily npm tavily-mcp
Relational, document, key-value, graph stores. Id Title Registry Identifier mongodbMongoDB npm mongodb-mcp-servermysqlMySQL npm mcp-server-mysqlneo4jNeo4j npm @johnymontana/neo4j-mcpredisRedis npm redis-mcpsupabaseSupabase npm supabase-mcptursoTurso npm mcp-server-tursoupstashUpstash npm @upstash/mcp-server
Dashboards, metrics, product analytics. Id Title Registry Identifier axiomAxiom npm mcp-server-axiomdatadogDatadog npm @winor30/mcp-server-datadogdynatraceDynatrace npm @dynatrace-oss/dynatrace-mcp-servergrafanaGrafana (Go binary via OCI) oci ghcr.io/grafana/mcp-grafanamixpanelMixpanel npm mixpanel-mcp-serverplausiblePlausible npm plausible-mcpprometheusPrometheus npm prometheus-mcp
Headless content platforms, blogs, marketing ops. Id Title Registry Identifier contentfulContentful npm @contentful/mcp-serverghostGhost npm ghost-mcphubspotHubSpot npm @hubspot/mcp-serversanitySanity npm @sanity/mcp-serverstrapiStrapi npm strapi-mcpwordpressWordpress npm wordpress-mcp
Chat, customer messaging, transactional email, SMS. Id Title Registry Identifier discordDiscord npm discord-mcpintercomIntercom (remote OAuth) remote (HTTP)resendResend npm resend-mcpsendgridSendGrid npm sendgrid-mcptelegramTelegram npm telegram-mcptwilioTwilio npm twilio-mcp
Payment processors, marketplaces, market data. Id Title Registry Identifier alpacaAlpaca npm alpaca-mcppaypalPayPal npm @paypal/mcppolygonPolygon npm polygon-mcpsalesforceSalesforce npm @salesforce/mcpshopifyShopify npm shopify-mcpstripeStripe npm @stripe/mcp
Containers, clusters, IaC, PaaS. Id Title Registry Identifier dockerDocker (daemon control) npm docker-mcpherokuHeroku npm @heroku/mcp-serverkubernetesKubernetes (cluster API) npm mcp-server-kubernetespulumiPulumi npm @pulumi/mcp-serverrailwayRailway npm @railway/mcp-serverterraformTerraform npm terraform-mcp-server
Public posting + metadata lookup. Id Title Registry Identifier linkedinLinkedIn npm linkedin-mcpredditReddit npm reddit-mcptiktokTikTok npm tiktok-mcptwitterTwitter npm twitter-mcpyoutubeYouTube npm youtube-mcp
Weather, recipes, news, music, general knowledge. Id Title Registry Identifier news-apiNewsAPI npm newsapi-mcpopenweatherOpenWeather npm openweather-mcprecipeRecipe npm recipe-mcpspotifySpotify npm spotify-mcpwolframWolfram npm wolfram-mcp
Text-to-image, model inference for images. Id Title Registry Identifier comfyuiComfyUI npm comfyui-mcpfalFal npm fal-mcpreplicateReplicate npm replicate-mcp
Embeddings stores + ANN search. Id Title Registry Identifier pineconePinecone npm @pinecone-database/mcpqdrantQdrant (Python via uvx) pypi mcp-server-qdrantturbopufferTurbopuffer npm @turbopuffer/turbopuffer-mcp
Ad platforms + email marketing. Id Title Registry Identifier google-adsGoogle Ads npm google-ads-mcpmailchimpMailchimp npm mailchimp-mcpmeta-adsMeta Ads npm meta-ads-mcp
Geospatial + routing. Id Title Registry Identifier mapboxMapbox npm @mapbox/mcp-server
Distribution mix Of the 105 entries:
102 ship as npm packages (stdio via npx).1 ships as pypi (qdrant, runs via uvx).1 ships as oci (grafana, Go binary in a container image).1 is a pure remote endpoint (intercom, OAuth streamable-http).
The catalog’s registry_type field is validated at build time — runner
is required for pypi packages and forbidden for every other registry
type.
Authentication Every server that needs credentials declares at least one
[[servers.env_vars]] entry with is_secret = true or false. The
env var names are visible in mcp-servers.toml^name = under your chosen server.
Nika never stores API tokens in workflow YAML. Secrets are read from
environment variables at run time. Use nika doctor to see which provider
variables are present or missing; it reports presence only and never prints
values.
See also
Verbs How invoke: routes to MCP tools + built-ins at runtime.
Builtins The 63 engine-native tools under nika:*.
Providers catalog LLM providers for the infer: and agent: verbs.
Error codes MCP errors — the spec’s NIKA-MCP namespace (NIKA-MCP-001 server unreachable · NIKA-MCP-002 call failed); the engine’s internal diagnostics registry stays engine-side.
