fetch_news

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

With no annotations provided, the description carries the burden of behavioral disclosure. It clearly states it won't modify read state and adds the non-obvious constraint that unsubscribed feedUrls are rejected. However, it doesn't mention what happens when no feedUrls are provided, whether includeConsumed changes default behavior, or any error/return specifics.

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 with zero waste. The first sentence front-loads the core action and side-effect-free nature; the second sentence adds the one critical constraint an agent must know before calling. Ideal length for this tool.

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?

Given there is no output schema and no annotations, the description is adequate but incomplete. It covers the read-only aspect and the subscription rule, but an agent is left guessing about filtering defaults, the meaning of includeConsumed, and error scenarios when invalid feedUrls are passed. Sibling names provide some context but not enough.

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 description adds limited parameter-level meaning: it explains that feedUrls must be subscribed. The schema already provides types, ranges, and formats for all parameters, so the description doesn't need to repeat that. But it doesn't clarify the interplay between filter parameters (e.g., category vs feedUrls) or the effect of includeConsumed.

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 ('latest news from local storage'), and clarifies a key behavioral nuance: it does not change read state. This distinguishes it from sibling tools like mark_read, though it doesn't explicitly name the 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 description implies this is the read-only counterpart to mark_read ('without changing read state') and implies a subscription prerequisite ('Unsubscribed feedUrls are not allowed'), but it doesn't explicitly say when to prefer this over request_sample_news or other siblings.

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