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

Annotations already declare readOnlyHint=false, openWorldHint=true, idempotentHint=false, and destructiveHint=false, so the mutation and safety profile is covered. The description adds one genuinely useful behavior beyond that: feeds are polled every 5 minutes, which sets expectations for how quickly content arrives. It does not say what happens if the URL already exists (relevant given idempotentHint=false), whether the feed is validated on add, or what is returned.

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 short sentences with zero redundancy, and the core action is front-loaded before the polling detail. 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 three-parameter tool with full schema coverage and annotations, the main missing pieces are duplicate-URL behavior and the fact that no output schema exists, so nothing tells the agent what a successful add returns (e.g., an identifier usable with remove_source or toggle_source). That is a real but modest gap for a tool this simple.

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 100%, so url, name, and industry_slug are all documented in the schema, and the description adds no syntax or format detail beyond restating that the URL must be an RSS/Atom feed. The defaulted industry_slug and its allowed slug values are left entirely to the schema, which is acceptable but not additive.

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 and resource ('Add a new RSS or Atom feed URL') plus its domain ('automated news monitoring'), which is enough to separate it from remove_source, list_sources, and toggle_source by verb alone. It never explicitly names a sibling or clarifies how it differs from enabling a global source, so it stops short of a 5.

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 phrase 'to automated news monitoring' implies the context in which to use it, but there is no explicit when-to-use/when-not guidance and no routing to alternatives. An agent facing the enable_global_source/disable_global_source siblings gets no help deciding whether to register a custom feed or toggle a built-in one.

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