Send a one-way text to the human's phone (push notification, no ring).
to is their 10-digit /call-me number. Pass a previous session_token to
stay in the same thread.
| Name | Required | Description | Default |
|---|---|---|---|
| to | Yes | ||
| body | Yes | ||
| from_label | No | Someone's AI | |
| session_token | No |
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
The description adds behavioral context beyond annotations by specifying it's a push notification with no ring and one-way (no response expected). It also explains thread continuation via session_token. This complements the destructiveHint and openWorldHint annotations without contradicting them.
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 sentences, front-loaded with the verb and purpose, followed by parameter clarifications. No unnecessary wording.
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 description covers the tool's core behavior and key parameters, and annotations handle safety. It doesn't document return values (no output schema) or failure behavior, but for a simple one-way messaging tool this is adequate. The unexplained from_label is a minor gap.
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?
With 0% schema coverage, the description compensates by explaining `to` as a 10-digit /call-me number and `session_token` for staying in the same thread. `body` is self-explanatory, but `from_label` remains unexplained, leaving a gap.
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 'Send' and clearly identifies the resource as a one-way text to the human's phone, with clarifying details (push notification, no ring) that distinguish it from sibling tools like call. The scope is unambiguous and not a tautology.
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 provides context for use (one-way text with no ring, session_token for threading) but does not explicitly mention alternatives or when not to use it relative to siblings like call or wait_for_reply. However, the context is clear enough to infer its place.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
Add one secure layer between your agents and this server.
Each tool has a clearly distinct purpose: call makes a voice call, poll_result checks on a ringing call, text sends a text, wait_for_reply waits for incoming messages, and set_thread_title names the thread. Even the two polling tools are differentiated by what they poll for (a call vs. general replies).
Tool names are all lower_snake_case but vary in structure: single verbs (call, text) vs. verb phrases (poll_result, set_thread_title, wait_for_reply). While readable, the pattern is not perfectly consistent across the set.
With 5 tools, the set is well-scoped for a personal communication server. Each tool covers a distinct and necessary capability without redundancy or bloat.
The surface covers the core workflows: initiating voice/text communication, polling for results, and waiting for replies. Minor gaps exist, such as no explicit thread history retrieval or ability to cancel a call, but these are workable.