placetel_send_smsSend SMS messages through the Placetel Web API by providing a recipient phone number and message body. Choose markdown or JSON output for the response.
Send SMS. (POST /sms)
| Name | Required | Description | Default |
|---|---|---|---|
| message | Yes | Body field message (required). | |
| recipient | Yes | Body field recipient (required). | |
| response_format | No | Output format: 'markdown' (human-readable, default) or 'json' (machine-readable). | markdown |
Changes observed during successful MCP inspections.
v1.0.1Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=false, openWorldHint=true, idempotentHint=false, so the safety profile is covered structurally. The description adds nothing further: no mention of cost/credits, delivery semantics (async vs. immediate), sender number requirements, or whether a retry duplicates the message despite non-idempotency.
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?
It is short and front-loaded, so there is no wasted prose, but the brevity is under-specification rather than efficiency. The POST endpoint parenthetical consumes the only secondary sentence slot instead of carrying useful invocation context.
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?
This is a mutating, open-world, non-idempotent action that sends real messages to real recipients, with no output schema to explain the result. For that risk profile the description is far too thin—no delivery confirmation behavior, error conditions, or sender identity information.
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 description coverage is 100%, so baseline is 3. However the schema itself is thin—'recipient' and 'message' are labeled only as body fields—and the description does not compensate with phone-number format (E.164), message length limits, or what the response_format enum means in practice.
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 "Send SMS. (POST /sms)" essentially restates the tool name and title, which is the textbook tautology case. The only extra information is an HTTP endpoint parenthetical that does not tell an agent anything about the operation's scope, target network, or result.
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?
No when-to-use guidance is offered, and no alternative is named. With siblings like placetel_initiate_call and placetel_create_fax in the same catalog, the description never clarifies that this is the text-messaging channel versus voice or fax pathways.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.