Weights & Biases
Read W&B Models projects, runs, sweeps, artifact types, reports, automations, integrations, teams, and organizations through the W&B Cloud GraphQL API.
Verdict
Common use cases
- Compare hyperparameters across experiment runs
- Retrieve artifact metadata for model lineage
- Summarize recent reports for sprint reviews
- Identify which run achieved target metrics
- List active automations and their triggers
Integration
- Vendor
- Weights & Biases
- Category
- developer-tools
- Auth
- API_KEY
- Tools
- 10
- Composio slug
weights_and_biases
Tools
- Get Current Viewer
Return the authenticated W&B user, default entity, and team names for connection context.
- Get Organization
Return a W&B organization's identifiers and organization entity by exact name.
- Get Team
Return a W&B team's identity and bounded membership metadata by exact team entity name.
- List Artifact Types
Return one page of artifact types defined in a W&B project.
- List Automations
Return one page of W&B automations accessible under an entity.
- List Integrations
List one page of Slack workspace/channel metadata and webhook integration names for a W&B entity. Webhook URLs and credentials are excluded.
- List Projects
Return one page of W&B projects visible under an entity.
- List Reports
Return one page of beta W&B reports for a project.
- List Runs
List one page of runs with IDs, display names, states, and creation times. Does not return run config, metrics, or history.
- List Sweeps
Return one page of hyperparameter sweeps from a W&B project when sweeps are enabled for the account.
Setup
Setup guide
- 11. In Switchy, open your workspace settings and navigate to the Integrations page. 2. Find Weights & Biases in the MCP catalog and click Connect. 3. You'll be prompted to paste a W&B API key — generate one by logging into wandb.ai, clicking your profile icon, selecting Settings, then scrolling to the API keys section and creating a new key. 4. Copy the key and paste it into Switchy's prompt, then click Authorize. 5. Switchy confirms the connection by fetching your default entity and team names. 6. Open any Project, type '@Weights & Biases list my projects' in the chat, and verify it returns your W&B project list. 7. If the response is empty or errors, double-check the API key has read access to the entities you need.
What teammates see: by default, memories from Weights & Biases are scoped to the Project (PROJECT visibility) - you can mark any memory PRIVATE or share it ORG-wide.
Works well with
Top models
Compatibility data appears once enough Projects have used this MCP together with a given model.
How Switchy teams use it
Starter prompts
Compare Recent Runs
@Weights & Biases show me the last five runs in the image-classifier project and compare their validation accuracy and training time.
Artifact Lineage Check
@Weights & Biases list all artifact types in the recommendation-engine project and tell me which versions were created this week.
Report Summary
@Weights & Biases get the latest reports for the nlp-experiments project and summarize the main takeaways from each.
Team Context Lookup
@Weights & Biases show me the team details for ml-platform-team and list the members with their roles.
Automation Audit
@Weights & Biases list all automations for the production entity and describe what each one does.
Example outputs
Illustrative - representative of the model's voice and quality, not literal recordings.
@wandb list all projects under our team entity and show me which ones have been updated in the last 30 days
Found 12 projects under entity 'acme-ml'. Recently active projects include: 'image-classifier-v2' (last run 2 days ago, 847 runs total), 'llm-finetuning' (last run 5 days ago, 203 runs), 'data-pipeline' (last run 12 days ago, 1,450 runs), and 'model-monitoring' (last run 18 days ago, 92 runs). The remaining 8 projects haven't logged runs in over 30 days. This represents the first page of results; pagination may be needed for teams with many projects.
This example demonstrates read-only project discovery. The MCP requires your W&B API key with at least viewer permissions on the entity. Results are paginated (typically 50 per page), so large teams may need follow-up queries. The 'last updated' inference comes from run metadata, not explicit project timestamps.
@wandb show me all artifact types in our 'image-classifier-v2' project and explain what each one tracks
The 'image-classifier-v2' project defines 4 artifact types: 'dataset' (versioned training/validation splits, 23 versions logged), 'model' (serialized PyTorch checkpoints, 15 versions), 'predictions' (inference output CSVs, 8 versions), and 'preprocessor' (feature transformation pipelines, 3 versions). Artifact types organize lineage tracking—datasets feed into model training runs, models generate predictions, and preprocessors ensure consistent feature engineering across environments. This is illustrative; actual version counts depend on your team's logging patterns.
Artifact types reveal your ML pipeline's structure. This read-only query helps audit what's being tracked and identify gaps (e.g., missing experiment configs). The MCP returns type metadata but not artifact contents—you'd need separate queries to inspect specific versions. Useful for onboarding new teammates to existing projects.
@wandb check our team's Slack integrations and draft a summary of which channels are receiving W&B notifications
Your entity 'acme-ml' has 3 Slack integrations configured: Workspace 'Acme Engineering' sends run completion alerts to #ml-experiments (webhook name 'exp-alerts'), model registry updates to #ml-prod (webhook 'registry-prod'), and sweep results to #hyperparameter-tuning (webhook 'sweep-notify'). Based on these channels, your team appears to separate experimental work (#ml-experiments, #hyperparameter-tuning) from production model changes (#ml-prod). Consider whether all three channels need active monitoring or if consolidation would reduce notification fatigue.
This synthesis example pairs W&B integration metadata with AI reasoning about team workflow. The MCP returns channel names and webhook identifiers but excludes sensitive URLs/credentials. Useful for auditing notification sprawl, but note that it won't show you the actual alert frequency or message content—just the configured destinations.
Use-case deep-dives
When distributed ML teams need shared training context
A 6-person ML team across two time zones runs long training jobs that span multiple shifts. The morning engineer needs to see what the overnight run produced without digging through Slack or local notebooks. This MCP wins here: the Get Current Viewer and List Projects tools let Switchy pull the team's active experiments and artifact lineage into a shared workspace where the next shift picks up context in under a minute. The List Reports tool surfaces the overnight team's summary without re-running queries. The threshold: if your team isn't already using W&B for experiment tracking, this MCP adds no value—it reads existing W&B state, it doesn't replace your tracking stack. For teams already on W&B who lose 20+ minutes per handoff reconstructing what happened, this is the buy.
When artifact provenance matters more than speed
A 3-person ML ops team at a fintech startup needs to document which models went to production and trace their training lineage for a quarterly audit. They're not debugging experiments—they're answering "where did this artifact come from" under time pressure. This MCP is the right call: List Artifact Types and List Projects give Switchy a read-only view into the registry without touching production infrastructure. The team can query artifact metadata and pull reports into a shared doc that auditors review. The trade-off: this MCP has no write access, so if you need to tag or annotate artifacts during the audit, you're back in the W&B UI. For read-only compliance pulls where the alternative is manual CSV exports, this saves 2-3 hours per audit cycle.
When new hires need W&B context without admin access
A senior ML engineer is onboarding a junior hire who needs to understand the team's experiment structure and automation setup but shouldn't have admin rights to the W&B workspace yet. The MCP's Get Team, List Automations, and List Integrations tools let Switchy surface a read-only map of how the team uses W&B—which Slack channels get notifications, which projects are active, what automations run on new artifacts—without granting the junior full workspace access. This works when onboarding is a 2-day sprint and the senior wants the junior to ask informed questions by day two. The boundary: if your W&B setup is simple enough to explain in a 10-minute screen share, skip this. For teams with 15+ projects and custom automation pipelines, this MCP turns onboarding into self-service.
Frequently asked
What does the Weights & Biases MCP do in Switchy?
It connects your team's W&B workspace so AI agents can query experiment metadata, list projects and artifact types, check automations, and pull report summaries. Agents can't trigger new runs or modify experiments — this is read-only access to your ML tracking data for analysis and debugging conversations.
Do I need admin access to connect Weights & Biases?
You need a W&B API key with read permissions on the entities (organizations or teams) you want agents to query. Any team member with access to those entities can generate a key from their W&B settings. Admin rights aren't required unless your W&B org restricts API key creation.
Can the MCP start training runs or log metrics to W&B?
No. The integration is read-only — agents can list projects, check artifact types, and pull automation configs, but they can't create runs, log metrics, or modify experiments. If you need write access, use the W&B Python SDK directly in a code execution environment.
How is this different from querying W&B through its API directly?
The MCP wraps W&B's GraphQL API into natural-language tools agents can call without you writing code. You get instant answers like "show me recent reports in project X" instead of crafting API requests. For programmatic workflows or write operations, the native API or SDK is still the right choice.
Who on the team should connect the W&B integration?
Whoever owns the ML experiments you want agents to reference. Typically an ML engineer or researcher with read access to the relevant W&B projects. The API key they provide determines which entities and projects agents can see, so choose someone whose permissions match your team's needs.