Get birth source evidence

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already cover read-only/idempotent/non-destructive, and the description adds auth requirements (source author's current farm access) and the partial-match behavior (producer selection required). That is meaningful context beyond the structured hints, though no pagination or response-shape notes.

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 tight sentences with the returned data front-loaded and constraints following. No filler, though the phrasing is jargon-dense enough that a first-time reader may need a second pass.

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?

With no output schema, the description still enumerates the main things returned (SMS source, media status, identity candidates) and the key precondition, so an agent can call it correctly. Gaps are limited to parameter-level detail and result paging.

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% for both parameters, so the description must carry the burden. It implies the source is an SMS record but never explains what source_sms_id or farm_id mean, their format, or when farm_id is optional versus required.

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 ('Read') plus three concrete resources: retained SMS birth source, ordered media status, and current-farm identity candidates. This is far more specific than the name alone, though it never explicitly contrasts with the close sibling get_birth_history_evidence.

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 a real precondition ('Requires the source author's current farm access') and a boundary ('this lookup does not approve identities or save a birth'), which tells the agent when not to expect a write. It stops short of naming an alternative tool for the approve/save path.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.