Subscribe an https endpoint to CRM events. events=['*'] for all, or a subset of ['contact.created','contact.updated','deal.created','deal.updated','deal.stage_changed']. Returns a secret ONCE - the subscriber verifies the Relm-Signature header (t=,v1=<hmac-sha256 of "t.body">). Deliveries retry with backoff and dead-letter after 6 attempts.
| Name | Required | Description | Default |
|---|---|---|---|
| url | Yes | ||
| events | No | ||
| enabled | No | ||
| description | No |
Changes observed during successful MCP inspections.
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
It discloses critical behavior: secret returned only once, signature verification format, retry with backoff and dead-letter after 6 attempts. This adds value beyond annotations, which only indicate non-read-only.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
Three sentences, front-loaded with the action, no fluff.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
Given no output schema and minimal param schema, the description covers purpose, event options, security handling, and delivery behavior, making it sufficient for an agent to invoke correctly.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema has zero descriptions. The description explains 'url' as the https endpoint and 'events' as a subset of listed event types, adding meaning. Params 'enabled' and 'description' remain implicit but are self-explanatory.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description states a specific verb+resource: 'Subscribe an https endpoint to CRM events.' This clearly identifies the tool as creating webhook subscriptions and distinguishes it from generic create tools and other webhook management tools.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
It provides clear context: subscribe an HTTPS endpoint to CRM events, with event options. Although it doesn't explicitly mention alternatives, the scope is well-defined for a webhook creation tool.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
Add one secure layer between your agents and this server.
