Post to this mailbox's active chat channel. Join a channel first; its channel cannot be supplied here.
Post to this mailbox's active chat channel. Join a channel first; its channel cannot be supplied here.
| Name | Required | Description | Default |
|---|---|---|---|
| date | No | ||
| message | Yes |
| Name | Required | Description | Default |
|---|---|---|---|
No arguments | |||
Changes observed during successful MCP inspections.
v1.4.0Input schema / properties / channelRemoved value: -{
- "title": "Channel",
- "type": "string"
-}Input schema / properties / channel_typeRemoved value: -{
- "anyOf": [
- {
- "type": "string"
- },
- {
- "type": "null"
- }
- ],
- "default": null,
- "title": "Channel Type"
-}Input schema / properties / with_agentRemoved value: -{
- "anyOf": [
- {
- "type": "string"
- },
- {
- "type": "null"
- }
- ],
- "default": null,
- "title": "With Agent"
-}Input schema / requiredPrevious value: -[
- "channel",
- "message"
-]New value: +[
+ "message"
+]v1.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the behavioral burden. It adds useful context by explaining the channel must be active/joined and cannot be passed as an argument, but it does not disclose effects, failure behavior when no channel is joined, or any permissions/limits.
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, front-loaded with the action and followed by the key constraint. No filler or redundant restatement of the schema.
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 simple two-parameter tool with an output schema, the description gives the essential invocation context: target, prerequisite, and a critical limitation. It is slightly incomplete only in parameter semantics, which is covered by the schema titles.
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 0%, so the description must compensate. It clarifies only that the channel is not supplied, while the two actual parameters (message and date) are not explained at all.
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 uses a specific verb and resource: 'Post to this mailbox's active chat channel.' It also notes the channel cannot be supplied, which differentiates it from channel-management siblings like iam_chat_join and from send/reply tools.
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?
It gives a clear prerequisite: 'Join a channel first.' It explains the target is the mailbox's active channel rather than a user-supplied one, but it does not explicitly name alternative tools or state when not to use this tool.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.