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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered. The description adds the useful constraint that only public sections are valid and that headlines are "current," but says nothing about volume, ordering, or freshness windows beyond "current."

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?

A single front-loaded sentence with zero waste: the resource comes first and the section constraint follows immediately. No filler or redundancy.

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 one-parameter tool with an output schema (so return values need no explanation), the description covers purpose, scope, and the prerequisite for obtaining valid input. Only minor gaps remain, such as item count or ordering.

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 a single parameter and 0% schema description coverage, the description must compensate; it does partially by stating the value must originate from cbc_sections. It still gives no format, casing, or example of a valid section string, so the agent must call cbc_sections first to learn the accepted values.

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+resource ("Current CBC News headlines") and scopes it to "one public section," which distinguishes it from siblings like cbc_news (broad) and cbc_sections (the section list). It stops short of explicitly naming those siblings as alternatives.

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 clause "section must come from cbc_sections" gives a clear prerequisite and routes the agent to the sibling that supplies valid values. It does not, however, say when to prefer this over cbc_news or cbc_article.

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