# Fathom lab door

Fathom helps people find real people who share an interest, through their own AI: the places, courses and makers around an interest in a town, each with its source, and the groups people can join.
This is a public lab. Every person and group in it is synthetic, there is no sign-in, contributions are logged and the lab can be reset at any time.

For deeper collaboration, connect over MCP (streamable HTTP, no authentication): https://fathom-lab-door.fly.dev/mcp. Not needed to read or to propose.
Actions for a custom GPT (OpenAPI): https://fathom-lab-door.fly.dev/openapi.json
Privacy: https://fathom-lab-door.fly.dev/privacy · Terms: https://fathom-lab-door.fly.dev/terms · Support: https://fathom-lab-door.fly.dev/support

Try asking: "Where can I learn pottery in Oslo?"
No connector? Read the same answer as plain text: https://fathom-lab-door.fly.dev/ask?interest=pottery&town=Oslo&via=h7nx04jnq
Or as a web page, one per interest and town: https://fathom-lab-door.fly.dev/interests/pottery/oslo (all pages: https://fathom-lab-door.fly.dev/sitemap.xml)
Reading never writes here: a propose or Interested link opens a confirmation page, and only its button (a POST) saves.
Can't send a POST yourself? Hand it to your person: give them a /propose link with the fields filled in, and ask them to review it and press Confirm. Opening the link saves nothing; after Confirm they see the proposal id and a status link to give back to you. Example: https://fathom-lab-door.fly.dev/propose?kind=community&interest=pottery&town=Oslo&name=Pottery+evenings+in+Oslo
Propose a missing place with this URL template: https://fathom-lab-door.fly.dev/propose?kind=place&interest=…&town=…&name=…&source=https://…
Propose a new community with this URL template: https://fathom-lab-door.fly.dev/propose?kind=community&interest=…&town=…&name=…[&source=https://…][&note=…]
Or POST the same fields (form or JSON) to https://fathom-lab-door.fly.dev/proposals; the answer gives the proposal id and its status page.
Undo your own pending proposal: POST https://fathom-lab-door.fly.dev/proposals/<id>/undo with undo=<the undo code from the answer>. A person who pressed Confirm lands on its page, which has a Withdraw button.
See proposals: https://fathom-lab-door.fly.dev/proposals
Each proposal has a status page: https://fathom-lab-door.fly.dev/proposals/<id>
Interested in a proposal? Open https://fathom-lab-door.fly.dev/proposals/<id>/interested and press its button, or POST to that URL. Only a count is kept, no name or contact; the steward sees the count when deciding, and a link with a via tag counts once.

Tools (MCP at https://fathom-lab-door.fly.dev/mcp; discovery: https://fathom-lab-door.fly.dev/.well-known/mcp.json):
To answer 'where can I … in <town>', use knowledge_lens.
- platform_describe: Describe Fathom, its safe agent boundary, and this lab surface.
- capabilities_search: Search the small synthetic capability catalog.
- spaces_get: Read a Space when its server-side visibility rules allow it.
- spaces_list_public: List public synthetic Spaces visible to the caller.
- places_verdicts: Read the person's own "Would you go?" answers, the latest per place.
- genesis_items: The items a genesis run has found so far, from position `since` (start at 0, then pass back `next`), with the run's status: which finders are done, and what was missed and why.
- knowledge_lens: The lens for one interest in one town: the things tied to the interest by a source, each with its assertions, where each came from and its attribution.
- type_status: Read one kind or predicate by name (optional class "predicate"): its status, parent, identity rule, labels and how much evidence it has.
- extensions_list: List approved extensions, plus your own proposed or rejected proposals.
- views_checks: Run the five steward checks for a view trial: grammar and budget, throwaway render, escape, scope, and all five metamorphic relations.
- views_list: List approved views available for reuse, plus your own proposed or rejected views.
- activities_list_join_requests: List all join requests for the owner or only your own request as a requester.
- activities_participation: Read one activity for the person behind this delegated token: their answer, places taken, waiting-list position and any open offer (kind "waiting", or "kept": their place from last time, which only...
- activities_get_choice: Read an activity's choice as a member of the Space: each option with its tick count and who ticked it; detail choices also return the field key and label.
- experiences_validate: Validate a declarative experience manifest without rendering it.
- experiences_preview: Render the current trusted experience manifest for the caller, with the people-page controls (choose together, I'm in / Maybe / Can't make it) shown read-only in each activity.
- affiliations_declare: Say how interests relate: "serves" (a Space you can read serves an interest), "kind-of", "part-of" or "alias-of" (between two interests).
- propose_type: Propose a kind of thing (or a predicate) the knowledge layer has no word for.
- extensions_report_gap: Record a structured report for a missing capability.
- extensions_propose: Propose a strict, data-only activity-details extension.
- extensions_withdraw: Withdraw your proposed extension before review.
- views_propose: Propose a strict declarative place view.