list_inboxList the user's email inbox threads (outbound demand-test sends + inbound replies / unsubscribes / complaints / bounces). Filter by tag.
| Name | Required | Description | Default |
|---|---|---|---|
| limit | No | max threads to return, ≤200 | |
| filter | No | default all | |
| offset | No | number of threads to skip (pagination) |
| Name | Required | Description | Default |
|---|---|---|---|
| result | Yes |
Changes observed during successful MCP inspections.
Input schema / properties / limit / descriptionAdded value: +"max threads to return, ≤200"Input schema / properties / offset / descriptionAdded value: +"number of threads to skip (pagination)"Output schema / (root)Previous value: -nullNew value: +{
+ "$schema": "http://json-schema.org/draft-07/schema#",
+ "additionalProperties": false,
+ "properties": {
+ "result": {}
+ },
+ "required": [
+ "result"
+ ],
+ "type": "object"
+}Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=true, so the description's statement of listing is consistent. Beyond that, the description does not disclose additional behavioral traits (e.g., pagination behavior, rate limits) but adds context on thread types. No contradiction with annotations.
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 that conveys the essential purpose and filter capability. Every word adds value with no redundancy.
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?
Given the existence of an output schema, the description does not need to explain return values. It sufficiently covers the tool's scope, filter, and context, making it complete for a list tool.
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 the schema already documents all parameters. The description mentions 'Filter by tag' but the schema's filter parameter with enum values already covers that. No additional meaning is added beyond what the schema provides.
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 that the tool lists the user's email inbox threads, specifying the types of threads (outbound demand-test sends, inbound replies, unsubscribes, complaints, bounces). This specific verb-resource-scope combination distinguishes it from siblings like list_site_inbox.
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 implies the tool is for the user's own email inbox but does not explicitly state when to use it versus alternatives such as list_site_inbox or list_test_inbox_addresses. No when-not or exclusion criteria are provided.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.