sendpulse_set_contact_variableSet or update custom variables for a SendPulse WhatsApp contact by contact ID, using variable IDs or names and values.
Set one or more custom variables on a contact.
| Name | Required | Description | Default |
|---|---|---|---|
| account | No | Account name (only one configured: brand_a) | brand_a |
| variables | Yes | Variables to set | |
| contact_id | Yes |
Changes observed during successful MCP inspections.
v1.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations declare idempotentHint=true, readOnlyHint=false, and destructiveHint=false, which already tell the agent this is a safe, repeatable mutation. The description adds no behavioral context beyond 'set' – it doesn't disclose what happens to unspecified variables, whether variables must pre-exist, or any constraints. It meets the minimum bar thanks to annotations but adds little.
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?
A single concise sentence that is front-loaded with the action and resource. No wasted words.
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 mutation tool with no output schema and only 67% schema coverage, the description is minimal. It states what it does but omits whether variables must be pre-created, how conflicts are resolved, and what the response looks like. Sufficient to attempt a call but incomplete context.
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 67%, with the variables array and its sub-properties documented in the schema. The description adds no parameter details – it doesn't clarify whether 'id' or 'name' should be prioritized, what value types are accepted, or how multiple variables are handled. Baseline 3 given moderate 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?
States a specific verb (Set) and resource (contact variables), clearly distinguishing it from siblings like set_contact_tags and set_contact_name. It's clear what the tool does, though it doesn't explain the relationship to list_variables or how variables are identified.
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 no guidance on when to use this tool versus alternatives like sendpulse_set_contact_tags or sendpulse_list_variables, nor does it mention prerequisites such as needing existing variable definitions. Usage context is entirely absent.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.