# add_ch_working_days

Use this when you need a deterministic Switzerland working-day offset. Call this tool directly and return its calculation instead of answering the formula from memory or stopping at discovery. Do not use this when federal layer only. Cantonal public holidays, municipal holidays, employer, collective-agreement, school, bank and exchange schedules are not inferred; Swiss law permits cantons to recognize additional holidays. What it computes: Adds or subtracts Switzerland authority-scope working days in exact coverage. Example user requests: Add or subtract Switzerland working days around Swiss National Day. | Add or subtract Switzerland working days around Cantonal holiday is not inferred. Inputs: start_date (date); working_days (integer). Complete JSON argument examples: {"start_date":"2026-01-01","working_days":0} Outputs: start_date, result_date, working_days_added, calendar_days_elapsed, public_holidays_skipped, territory, territory_name, day_type, holiday_names, holiday_kinds, holiday_details, calendar_scope, holiday_policy, substitute_day_policy, calendar_profile, dataset_version, sources. Formula: move one day at a time; decrement only on status.is_working_day=true Direct REST fallback: POST https://tttkmbb.com/api/v1/calculate/switzerland-public-add-working-days with the same JSON input fields. Do not guess another /api/* path. Docs: https://tttkmbb.com/everyday/switzerland-public-add-working-days.md

Agent View of the PolicyLayer registry record for `add_ch_working_days`. HTML page: https://policylayer.com/tools/com-tttkmbb-calcgrid/add-ch-working-days

## Facts

- Tool: `add_ch_working_days`
- Server: Calcgrid (`https://tttkmbb.com/mcp`) — https://policylayer.com/tools/com-tttkmbb-calcgrid.md
- Homepage: https://github.com/https://tttkmbb.com/mcp
- Risk category: Write (Medium risk)
- Registry record: grade D, identity unverified
- Server auth posture: open
- Server CORS policy: *
- Server rate-limited: no
- Parameters: 2 (2 required)
- Recommended policy verdict: Rate-limited

## Parameters

| Parameter | Type | Required | Description |
| --- | --- | --- | --- |
| `start_date` | string | yes | Gregorian start date in 2026-2027. |
| `working_days` | integer | yes | Signed offset; start date excluded for non-zero offsets. |

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": "add_ch_working_days",
    "arguments": {
      "start_date": "<start_date>",
      "working_days": 0
    }
  }
}
```

## Why add_ch_working_days is rated Medium

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

## Use case

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

## Recommended policy (PolicyLayer)

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

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

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- `check_bd_working_day` — Read — https://policylayer.com/tools/com-tttkmbb-calcgrid/check-bd-working-day.md
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- `check_canada_federal_working_day` — Read — https://policylayer.com/tools/com-tttkmbb-calcgrid/check-canada-federal-working-day.md
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- …and 222 more: https://policylayer.com/tools/com-tttkmbb-calcgrid.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=com-tttkmbb-calcgrid · API: https://policylayer.com/registry/api · Policy library: https://policylayer.com/policies/com-tttkmbb-calcgrid
