Customize

List marketplaces

The marketplaces a workspace reads plugins from, in the open plugin format (.claude-plugin/marketplace.json): each with its name (the @marketplace part of a plugin's ref), source (github with repo, g1t with repo, git or url with url, or builtin), builtin (every workspace has it and it cannot be removed: claude-plugins-official, anthropic-agent-skills and g1t), about, owner, how many plugins it lists, fetched_at and problem (why its manifest could not be read, when it could not), who added it and when, and can_remove.

GET/workspaces/{workspace}/customize/marketplaces

Members only.

Every workspace reads claude-plugins-official, anthropic-agent-skills and g1t, which are builtin and cannot be removed. source is the marketplace’s source object in the open plugin format: github (repo), g1t (repo, a repository here), git or url (url), or builtin. problem says why the manifest could not be read last time, if it could not. See Customize.

Authentication: Required. Send an access token as Authorization: Bearer.
MCP tool: customize with action list_marketplaces, and the same inputs
Scope: An access token needs workspace:read.

Path parameters

Name	Type	Required	Description
`workspace`	string	Yes	The workspace’s slug.

Example request

curl https://api.g1t.sh/workspaces/flagon-io/customize/marketplaces \
  -H "Authorization: Bearer $G1T_TOKEN"

Example response

A successful request answers 200 with:

[
  {
    "name": "claude-plugins-official",
    "source": {
      "source": "github",
      "repo": "anthropics/claude-plugins-official"
    },
    "builtin": true,
    "about": "Official plugins from Anthropic.",
    "owner": "Anthropic",
    "plugins": 42,
    "fetched_at": "2026-10-11T14:02:11.408Z",
    "problem": null,
    "added_by": null,
    "added_at": null,
    "can_remove": false
  },
  {
    "name": "flagon-tools",
    "source": {
      "source": "g1t",
      "repo": "flagon-io/plugins"
    },
    "builtin": false,
    "about": "Flagon's own skills and connectors.",
    "owner": "Flagon",
    "plugins": 3,
    "fetched_at": "2026-10-11T14:02:12.117Z",
    "problem": null,
    "added_by": "syntaqx",
    "added_at": "2026-10-09T18:20:03.512Z",
    "can_remove": true
  }
]

Errors

A failed request answers with one of these statuses and a body like {"error": {"code": "not_found", "message": "Repository not found."}}. See errors.

Status	Code	When
401	`unauthenticated`	A token is required, or the one sent is not valid.
403	`forbidden`	The token is valid but not allowed to do this, such as a member-only change or an agent token outside its repository.
404	`not_found`	It does not exist, or you cannot see it.
422	`invalid`	The input is not valid. `message` says which field and why.