add_suppressionAdd an address to the suppression list.
| Name | Required | Description | Default |
|---|---|---|---|
| Yes | Email address to stop sending to | ||
| reason | No | Optional note on why the address is suppressed | |
| tenant | No | Add to this tenant's own list instead of the account's. The tenant's external id (your id for that customer) or its Groundmail id |
| Name | Required | Description | Default |
|---|---|---|---|
| suppression | Yes | The suppression entry |
Changes observed during successful MCP inspections.
Input schema / properties / tenantAdded value: +{
+ "description": "Add to this tenant's own list instead of the account's. The tenant's external id (your id for that customer) or its Groundmail id",
+ "type": "string"
+}Output schema / properties / suppression / properties / tenantAdded value: +{
+ "description": "External id of the tenant, on an entry of a tenant's own suppression list",
+ "type": "string"
+}Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already disclose that this is destructive, non-read-only, idempotent, and closed-world. The description adds no behavioral context beyond those annotations, and for a destructive suppression tool it should at least state that the address will stop receiving email.
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 front-loaded sentence with no wasted words. It is efficient, though it is under-specified rather than richly concise.
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 tool has a complete schema, rich annotations, and an output schema, so the description does not need to explain return values. However, for a destructive suppression mutation with tenant scoping, the description should mention the impact and the account-vs-tenant choice.
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 all three parameters are already documented in the input schema. The description adds no additional parameter semantics, which makes the baseline of 3 appropriate.
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 and resource: adds an address to the suppression list. It is clear enough to distinguish from list_suppressions and remove_suppression, though the description does not explicitly name those siblings.
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?
There is no explicit when-to-use guidance, no alternatives, and no mention of prerequisites such as whether the address must be validated or whether tenant-scoped suppression differs from account-level suppression.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
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