get_birth_source_evidence

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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false, so the safety profile is covered. The description adds meaningful behavioral context beyond annotations: it requires the source author's current farm access, partial/ambiguous matches require producer selection, and it explicitly states this lookup does not approve identities or save a birth. This clarifies side-effect boundaries and access requirements.

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?

Three sentences with no waste. The core action and resource are front-loaded, followed by access requirements and explicit non-effects. Every sentence earns its place.

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 read-only lookup with two parameters and no output schema, the description covers the access requirement, the ambiguity handling, and the non-effects. It doesn't describe return values, but with no output schema and a read-only annotation, the description is reasonably complete. A small gap is not explaining what 'current-farm identity candidates' means or how producer selection is performed.

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 carries the burden for parameter meaning. The description mentions 'source author's current farm access' and 'producer selection', which hints at the farm_id parameter's role, but it doesn't explicitly explain source_sms_id or farm_id formats or semantics beyond the schema's uuid format. Baseline 3 is appropriate because the description adds some context but doesn't fully compensate for the 0% schema coverage.

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 states a specific verb ('Read') and resource ('retained SMS birth source, ordered media status, and current-farm identity candidates'), which clearly distinguishes it from sibling tools like get_birth_history_evidence or confirm_birth_event. It doesn't explicitly name a sibling, but the resource and scope are specific enough to differentiate.

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 gives clear context: it requires the source author's current farm access, and it notes that partial/ambiguous matches require producer selection. It doesn't explicitly say when to use this vs alternatives, but the 'requires' and 'does not approve identities or save a birth' exclusions provide practical usage boundaries.

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