fetch_feed

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

Annotations already establish this as a safe, read-only, idempotent operation. The description adds useful behavioral detail beyond that: it returns feed-level metadata plus structured entries and auto-detects RSS vs Atom. It does not discuss error or network edge cases, but the annotation safety profile lowers the burden.

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?

The description is two tight sentences with no filler. It front-loads the core action, then efficiently provides the return contract and the auto-detection behavior.

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?

There is no output schema, so the description responsibly enumerates the returned metadata and entry fields. For a network tool with several optional tuning parameters, it leaves default/error behavior to the schema, but the core invocation trigger and return shape are sufficiently complete.

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 only 43% schema description coverage and seven parameters, the description needed to compensate but does not. It says nothing about limit, max_bytes, timeout_ms, user_agent, max_redirects, or allow_private_hosts beyond what the schema already provides. The URL parameter is only implied by 'feed'.

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 uses a specific verb ('Fetch and parse') tied to a well-defined resource ('RSS 2.0 or Atom 1.0 feed') and enumerates the exact return shape. This clearly separates fetch_feed from the HTML, metadata, sitemap, and generic HTTP sibling tools.

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 intended use case is implied by naming RSS/Atom feeds, but the description never explicitly says when to choose this over fetch_reader, http_get, or fetch_meta, nor does it state when not to use it. There's context, but no explicit routing or exclusions.

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