Postbye MCP
An official MCP server provided by Postbye that allows AI assistants to access cancellation guides, mailing addresses, and formal letter templates for over 10,000 companies. It enables agents to search for companies, retrieve specific cancellation instructions, and generate formal cancellation letters to be mailed via certified post.
Endpoint and access
No sign-in to connect and list tools. Individual tools may still need a vendor account, credentials, or permissions; check the documented prerequisites.
https://postbye.com/mcpWhat you can do with it
- Search for a company's cancellation guide
- Retrieve mailing addresses for subscription cancellation
- Generate formal cancellation letter text
- List available cancellation categories
Source and maintenance
Protocol and capabilities
- Server
- postbye 1.2.0
- MCP protocol
- 2025-06-18
- Tools
- 4 advertised
- Resources
- Not advertised
- Resource templates
- Not advertised
- Prompts
- Not advertised
{
"tools": {
"listChanged": false
}
}Server-provided instructions
Untrusted server output shown for inspection. It is not Koskamo guidance and is excluded from knowledge search.
Tools
4 advertised
search_companies — Search cancellation guides
Find companies by name (for example "netflix" or "planet fitness") among the subscriptions and memberships Postbye has a cancellation guide for. Returns each match's slug, category, how the company takes cancellations and the guide URL. Use the slug with get_cancellation_guide.
{
"type": "object",
"required": [
"query"
],
"properties": {
"limit": {
"type": "integer",
"default": 5,
"maximum": 10,
"minimum": 1,
"description": "Maximum number of matches (1 to 10)."
},
"query": {
"type": "string",
"maxLength": 100,
"minLength": 1,
"description": "Company or service name, or part of it."
}
},
"additionalProperties": false
}{
"title": "Search cancellation guides",
"readOnlyHint": true,
"openWorldHint": false,
"idempotentHint": true,
"destructiveHint": false
}get_cancellation_guide — Get a cancellation guide
How to cancel one company's subscription or membership: how it takes cancellations, the notice period, the traps to check first, billing-partner notes, sources, when the facts were verified, the mailing address(es) on file and the guide and address page URLs. Accepts a company slug from search_companies (merged duplicate slugs resolve to the current one).
{
"type": "object",
"required": [
"slug"
],
"properties": {
"slug": {
"type": "string",
"maxLength": 100,
"minLength": 1,
"description": "Company slug, for example \"netflix\"."
}
},
"additionalProperties": false
}{
"title": "Get a cancellation guide",
"readOnlyHint": true,
"openWorldHint": false,
"idempotentHint": true,
"destructiveHint": false
}get_cancellation_letter — Get a cancellation letter
A plain-text cancellation letter for one company, built from the same template as Postbye's free letter tool, plus where to send it. Fields not supplied stay as [bracketed placeholders] to fill in. Nothing is stored.
{
"type": "object",
"required": [
"slug"
],
"properties": {
"slug": {
"type": "string",
"maxLength": 100,
"minLength": 1,
"description": "Company slug from search_companies."
},
"customer_name": {
"type": "string",
"maxLength": 100,
"description": "Your full name as it appears on the account (optional)."
},
"account_number": {
"type": "string",
"maxLength": 64,
"description": "Account, membership or reference number (optional)."
}
},
"additionalProperties": false
}{
"title": "Get a cancellation letter",
"readOnlyHint": true,
"openWorldHint": false,
"idempotentHint": true,
"destructiveHint": false
}list_categories — List guide categories
The category hubs of the cancellation guides (streaming, gyms, phone and internet, insurance and more) with the number of guides in each and the hub URL.
{
"type": "object",
"properties": {},
"additionalProperties": false
}{
"title": "List guide categories",
"readOnlyHint": true,
"openWorldHint": false,
"idempotentHint": true,
"destructiveHint": false
}Prompts
Not advertised
Resources
Not advertised
30-day availability
Aggregated from read-only remote checks; this is not a tool-execution or security guarantee.
- Successful checks
- 1 of 1 (100%)
- Average latency
- 480 ms
- 95th percentile latency
- 480 ms
Maintenance history
Public check and source-refresh events. Editorial and ownership records remain private.
- · probe · passed · 480 ms · metadata changed · 4 tool(s)
Connect from your client
Each snippet registers the same endpoint; pick the client you use.
Claude Code
claude mcp add --transport http postbye-mcp https://postbye.com/mcpCodex
codex mcp add postbye-mcp --url https://postbye.com/mcpCursor
{
"mcpServers": {
"postbye-mcp": {
"url": "https://postbye.com/mcp"
}
}
}Cline
{
"mcpServers": {
"postbye-mcp": {
"type": "streamableHttp",
"url": "https://postbye.com/mcp",
"disabled": false
}
}
}VS Code
{
"servers": {
"postbye-mcp": {
"type": "http",
"url": "https://postbye.com/mcp"
}
}
}Gemini CLI
gemini mcp add --transport http postbye-mcp https://postbye.com/mcpClaude Desktop
{
"mcpServers": {
"postbye-mcp": {
"url": "https://postbye.com/mcp"
}
}
}Windsurf
{
"mcpServers": {
"postbye-mcp": {
"serverUrl": "https://postbye.com/mcp"
}
}
}Let your agent find its tools
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