Retrieve a saved WhatsApp contact by JID to view its saved name, push name, and business name. Read-only; returns the contact object.
Get one saved contact by JID: saved name, push name and business name. Read-only. Returns the contact object.
| Name | Required | Description | Default |
|---|---|---|---|
| id | Yes | Contact JID |
Changes observed during successful MCP inspections.
v2.0.0Input schema / properties / contactIdRemoved value: -{
- "description": "Contact ID (phone number with @s.whatsapp.net)",
- "type": "string"
-}Input schema / properties / idAdded value: +{
+ "description": "Contact JID",
+ "type": "string"
+}Input schema / requiredPrevious value: -[
- "contactId"
-]New value: +[
+ "id"
+]Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=true and openWorldHint=true, so 'Read-only' merely restates structured data. The description does add that the returned object contains saved name, push name, and business name, but says nothing about failure modes for an unmatched JID despite openWorldHint implying external lookups.
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?
Two short sentences with no filler, front-loading the identity and scope of the operation before the return note. Nothing extraneous, though also nothing especially well-structured.
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?
For a single-parameter read tool with full annotation coverage and no output schema, the description covers identity, scope, and the main return fields. Only the not-found behavior is left unspecified, which is a minor gap at this complexity level.
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 coverage is 100% with a single documented parameter ('Contact JID'), so the schema already carries the semantics. 'By JID' adds no format, validation, or lookup detail beyond the schema description.
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?
States a specific verb (Get) and resource (one saved contact), and enumerates the returned fields (saved name, push name, business name). The word 'one' implicitly distinguishes it from the sibling whatsapp_get_contacts, though it never names that sibling explicitly.
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?
Usage is only implied by 'Get one saved contact by JID' — the single-lookup case. It never states when to prefer this over whatsapp_get_contacts, whatsapp_get_user_profile, or whatsapp_check_user, nor what happens for an unknown JID.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.