# create_experiment

[SUPPORT] 3f6b8715 — W1-M Experiment Registry: create a named experiment (a research question; many runs belong to one). Reuses the pre-existing experiments table (4376e655) additively — config_template/created_by (an unrelated ML-style tracking interface's own columns) are left untouched. Persistent-state disclosure: on hosted Meridian, supplied text and project/session metadata -- including task log entries, pinned decisions, sprint items, notes, handoff/goal state, and HITL queue items -- are sent to and stored in Meridian's service, in an isolated per-tenant Postgres database (Neon); self-hosted deployments keep the same categories in the configured local SQLite/Postgres database. This data is visible in the dashboard and API, and may resurface in later project context or handoffs. Notes and pinned decisions can be deleted individually; task log entries and sprint items can be deleted via the dashboard/API (not exposed as an agent-facing tool); HITL queue items and handoff state have no per-record delete. Full removal of any of this data is available via project or account deletion, using the documented controls. Do not include secrets.

Agent View of the PolicyLayer registry record for `create_experiment`. HTML page: https://policylayer.com/tools/io-github-ajc3xc-meridian/create-experiment

## Facts

- Tool: `create_experiment`
- Server: Meridian (`@meridianmcp/mcp`) — https://policylayer.com/tools/io-github-ajc3xc-meridian.md
- Install: `npx -y @meridianmcp/mcp`
- Homepage: https://github.com/meridianmcp/Meridian
- Risk category: Write (Medium risk)
- Registry record: grade D, identity unverified
- Server auth posture: gated
- Server CORS policy: *
- Server rate-limited: no
- Parameters: 5 (1 required)
- Recommended policy verdict: Rate-limited

## Parameters

| Parameter | Type | Required | Description |
| --- | --- | --- | --- |
| `name` | string | yes | Bounded, non-empty experiment name. |
| `hypothesis` | string | no | What this experiment is testing. |
| `project_id` | string | no |  |
| `session_id` | string | no |  |
| `project_name` | string | no | Project name — an alternative to project_id; resolved to the id internally. project_id wins if both are given. |

Parameters from the server's own tool schema.

## Example call (MCP tools/call, JSON-RPC 2.0)

```json
{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "create_experiment",
    "arguments": {
      "name": "<name>"
    }
  }
}
```

## Why create_experiment is rated Medium

An AI agent can call create_experiment faster than any human can review: one bad instruction and it creates or modifies resources in Meridian by the hundred, each call as confident as the last.

## Use case

AI agents use create_experiment to create or update resources in Meridian, usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Meridian environment.

## Recommended policy (PolicyLayer)

Verdict: **Rate-limited**. Enforced by the PolicyLayer MCP gateway (https://policylayer.com/mcp-gateway) before a call reaches Meridian:

```json
{
  "version": "1",
  "default": "deny",
  "tools": {
    "create_experiment": {
      "limits": [
        {
          "counter": "create_experiment_rate",
          "window": "minute",
          "max": 30,
          "scope": "grant"
        }
      ]
    }
  }
}
```

## Other tools on Meridian (234)

- `accept_handoff` — Destructive — https://policylayer.com/tools/io-github-ajc3xc-meridian/accept-handoff.md
- `acquire_docx_document_lease` — Destructive — https://policylayer.com/tools/io-github-ajc3xc-meridian/acquire-docx-document-lease.md
- `answer_hitl` — Destructive — https://policylayer.com/tools/io-github-ajc3xc-meridian/answer-hitl.md
- `batch_mutate` — Destructive — https://policylayer.com/tools/io-github-ajc3xc-meridian/batch-mutate.md
- `capture_research_finding` — Destructive — https://policylayer.com/tools/io-github-ajc3xc-meridian/capture-research-finding.md
- `checkpoint` — Destructive — https://policylayer.com/tools/io-github-ajc3xc-meridian/checkpoint.md
- `claim_docx_region` — Destructive — https://policylayer.com/tools/io-github-ajc3xc-meridian/claim-docx-region.md
- `claim_file` — Destructive — https://policylayer.com/tools/io-github-ajc3xc-meridian/claim-file.md
- `claim_sprint_item` — Destructive — https://policylayer.com/tools/io-github-ajc3xc-meridian/claim-sprint-item.md
- `clear_capability_profile` — Destructive — https://policylayer.com/tools/io-github-ajc3xc-meridian/clear-capability-profile.md
- `clone_profile_layer` — Destructive — https://policylayer.com/tools/io-github-ajc3xc-meridian/clone-profile-layer.md
- `delete_custom_hook` — Destructive — https://policylayer.com/tools/io-github-ajc3xc-meridian/delete-custom-hook.md
- `delete_note` — Destructive — https://policylayer.com/tools/io-github-ajc3xc-meridian/delete-note.md
- `delete_sprint_item_pointer` — Destructive — https://policylayer.com/tools/io-github-ajc3xc-meridian/delete-sprint-item-pointer.md
- `delete_watchlist_query` — Destructive — https://policylayer.com/tools/io-github-ajc3xc-meridian/delete-watchlist-query.md
- `dismiss_hitl` — Destructive — https://policylayer.com/tools/io-github-ajc3xc-meridian/dismiss-hitl.md
- `fan_out_sprint_items` — Destructive — https://policylayer.com/tools/io-github-ajc3xc-meridian/fan-out-sprint-items.md
- `idle_until_all_done` — Destructive — https://policylayer.com/tools/io-github-ajc3xc-meridian/idle-until-all-done.md
- `index_equation` — Destructive — https://policylayer.com/tools/io-github-ajc3xc-meridian/index-equation.md
- `index_figure` — Destructive — https://policylayer.com/tools/io-github-ajc3xc-meridian/index-figure.md
- `index_table` — Destructive — https://policylayer.com/tools/io-github-ajc3xc-meridian/index-table.md
- `ingest_document` — Destructive — https://policylayer.com/tools/io-github-ajc3xc-meridian/ingest-document.md
- `ingest_document_structure` — Destructive — https://policylayer.com/tools/io-github-ajc3xc-meridian/ingest-document-structure.md
- `link_figure_caption` — Destructive — https://policylayer.com/tools/io-github-ajc3xc-meridian/link-figure-caption.md
- `link_flag_to_section` — Destructive — https://policylayer.com/tools/io-github-ajc3xc-meridian/link-flag-to-section.md
- `link_proposal_lineage` — Destructive — https://policylayer.com/tools/io-github-ajc3xc-meridian/link-proposal-lineage.md
- `link_table_caption` — Destructive — https://policylayer.com/tools/io-github-ajc3xc-meridian/link-table-caption.md
- `log_task` — Destructive — https://policylayer.com/tools/io-github-ajc3xc-meridian/log-task.md
- `purge_ai_log` — Destructive — https://policylayer.com/tools/io-github-ajc3xc-meridian/purge-ai-log.md
- `receive_messages` — Destructive — https://policylayer.com/tools/io-github-ajc3xc-meridian/receive-messages.md
- …and 204 more: https://policylayer.com/tools/io-github-ajc3xc-meridian.md

## For agents

This record is a snapshot. Live verdicts and the full registry:

- Check every server in your MCP config at once: `npx -y policylayer stack`
- Vet a server before you add it: install the mcp-precheck skill — `npx skills add https://policylayer.com` (skill text: https://policylayer.com/skill.md)
- Query the registry over MCP: endpoint `https://api.policylayer.com/mcp` — tools `check_mcp_server`, `check_mcp_stack`, `check_tool`, `search_registry`, `get_change_events`

---

Source: the PolicyLayer MCP registry — one continuously verified record per MCP server. Full record: https://policylayer.com/registry?q=io-github-ajc3xc-meridian · API: https://policylayer.com/registry/api · Policy library: https://policylayer.com/policies/io-github-ajc3xc-meridian