Invoke an endpoint in the Telnyx TypeScript API. Note: use the list_api_endpoints tool to get the list of endpoints and get_api_endpoint_schema tool to get the schema for an endpoint.
| Name | Required | Description | Default |
|---|---|---|---|
| args | Yes | The arguments to pass to the endpoint. This must match the schema returned by the `get_api_endpoint_schema` tool. | |
| endpoint_name | Yes | The name of the endpoint to invoke. |
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
The description adds no behavioral context beyond the annotations. It does not mention side effects, authentication needs, rate limits, or expected outcomes. The annotations already indicate destructive/read-write behavior, but the description does not elaborate on implications for the agent.
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?
The description is extremely concise, consisting of two sentences that convey purpose and usage guidance without any fluff. It is front-loaded with the primary action and immediately follows with helpful pointers.
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?
The description is adequate for a generic invocation tool, especially with the reference to helper tools for endpoint discovery and schema. However, it does not mention response handling, error conditions, or the need for authentication, which would make it more complete given the tool's broad scope.
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?
The input schema fully describes both parameters (endpoint_name and args), including the need for args to match the endpoint schema. The description does not add extra semantic detail but references the schema tool, which is enough to satisfy a baseline score given 100% schema coverage.
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 clearly states the tool's function with a specific verb ('Invoke') and resource ('endpoint in the Telnyx TypeScript API'). It also distinguishes itself from sibling tools like list_api_endpoints and get_api_endpoint_schema, which serve discovery purposes.
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?
The description provides explicit guidance by pointing to list_api_endpoints for obtaining the endpoint list and get_api_endpoint_schema for the schema, implying that invoke_api_endpoint is used after these. However, it does not state when not to use this tool, so it falls short of a perfect score.
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.
All tools have distinct purposes: the first three are for inspecting and invoking the Telnyx API endpoints, while the last three launch separate MCP apps for specific domains. There is no overlap or ambiguity.
Tool names follow two consistent patterns: 'verb_api_endpoint' for API operations and 'open_<app_name>' for launching apps. While patterns differ, they are each internally consistent and clearly indicate the tool's category.
With 6 tools, the server is well-scoped. The API exploration tools cover essential operations (list, schema, invoke), and the app launcher tools provide access to specialized features without overloading the tool list.
The server provides a complete surface for its purpose: full API endpoint discovery and invocation, plus launching dedicated apps for number intelligence, usage/cost analysis, and voice monitoring. No obvious gaps.
