read_headlines

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

Annotations already cover read-only, open-world, idempotent, and non-destructive traits. The description adds meaningful context beyond those: the daily-edition format, the default-to-latest behavior, and the fact that it is written by the build agent and disclosed in the footer. No contradictions with annotations.

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 carry high signal with no filler: purpose is front-loaded, the parameter usage is stated compactly, and the authorship disclosure is one short clause. 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 simple read-only tool with one optional parameter and no output schema, the description is complete: it covers content, default behavior, date formatting, and source attribution. An agent has enough information to call it correctly without further inference.

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 schema only defines a date pattern, but the description adds the key semantic that omitting date returns the latest edition and passing date targets a specific day. This compensates well for the 0% schema description coverage, though it does not cover error behavior for invalid dates.

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 names a specific verb ('Read') and a distinct resource ('The Headlines: one daily edition'), and details exactly what the edition contains: moved threads, outside events, and new voices. This makes it easy for an agent to distinguish from sibling reading tools like read_discussion or read_voice.

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 clearly states the default behavior (latest edition) and the optional date parameter, which tells an agent how to invoke it. However, it gives no explicit guidance on when to choose this tool over siblings like catch_up or followed_feed, leaving exclusion criteria implicit.

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