list_sendersList sender names
List sender IDs (max 11 chars) the account may use in send_sms.from. Status active is ready; pending awaits carrier registration.
| Name | Required | Description | Default |
|---|---|---|---|
No arguments | |||
| Name | Required | Description | Default |
|---|---|---|---|
| data | No | ||
| current | No | ||
| request_new_url | No |
Changes observed during successful MCP inspections.
Output schema / (root)Previous value: -nullNew value: +{
+ "$schema": "http://json-schema.org/draft-07/schema#",
+ "additionalProperties": {},
+ "properties": {
+ "current": {},
+ "data": {
+ "items": {
+ "additionalProperties": {},
+ "properties": {},
+ "type": "object"
+ },
+ "type": "array"
+ },
+ "request_new_url": {
+ "type": "string"
+ }
+ },
+ "type": "object"
+}Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint, idempotentHint, and destructiveHint. The description adds useful behavioral detail beyond annotations by explaining the 11-character limit and what active/pending statuses mean, helping the agent interpret results.
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?
Extremely concise: a clear one-line summary followed by the only relevant behavioral details. No filler, no repetition of schema, and each sentence adds value.
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 a zero-parameter read-only tool with an output schema, the description covers everything an agent needs: what is listed, the length constraint, the status semantics, and the relationship to send_sms.from. Nothing important is missing.
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?
The tool has zero parameters and schema coverage is 100%, so there are no parameter semantics to document. Per baseline for zero-parameter tools, this is appropriately handled.
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: 'List sender names' / sender IDs, and clarifies these are the identifiers usable in send_sms.from. This clearly differentiates it from sibling tools like set_default_sender or send_sms.
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?
Gives practical context: these senders are what the account may use in send_sms.from, and explains the meaning of 'active' vs 'pending' status. It does not explicitly name alternatives or say when not to use it, but the context is sufficient for a zero-parameter list tool.
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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