subscribe_feed

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It states the action ('subscribe') but doesn't explain what happens after subscription (e.g., whether feeds are fetched immediately, if errors occur for invalid URLs, or if it returns a confirmation). For a mutation tool with zero annotation coverage, this is a significant gap in transparency.

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 a single, efficient sentence in Chinese ('订阅新的 RSS 源'), which directly conveys the core purpose without any wasted words. It's front-loaded and appropriately sized for the tool's function.

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 the tool has no annotations, no output schema, and involves mutation (subscription), the description is incomplete. It doesn't cover behavioral aspects like error handling, return values, or side effects (e.g., how the feed integrates with other tools like 'get_feeds'). For a 4-parameter tool with this complexity, more context is needed.

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 the schema fully documents all parameters (feed_url, category_id, login, password). The description adds no additional meaning beyond the schema, such as explaining parameter interactions (e.g., login/password are only needed for authenticated feeds) or usage examples. Baseline 3 is appropriate when the schema does the heavy lifting.

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 clearly states the action ('订阅' meaning 'subscribe') and the resource ('新的 RSS 源' meaning 'new RSS feed'), making the purpose immediately understandable. It doesn't explicitly differentiate from sibling tools like 'unsubscribe_feed' or 'get_feeds', but the verb 'subscribe' versus 'unsubscribe' or 'get' provides inherent differentiation.

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 provides no guidance on when to use this tool versus alternatives like 'get_feeds' (to list existing feeds) or 'unsubscribe_feed' (to remove feeds). It also doesn't mention prerequisites, such as needing an existing feed URL or authentication details for protected feeds, leaving usage context unclear.

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