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

The description goes beyond annotations by disclosing the re-baseline side effect when feedUrl changes: check state resets, only items published after the change are posted, and backlog flooding is avoided. This directly informs agent reasoning about a mutating side effect. It also states 'partial update,' which tells the agent that omitted fields retain existing values. No contradiction with annotations.

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?

Three sentences, front-loaded with the core action, followed by a behavioral caution and a use-this-when clause. No redundant or filler content; the re-baseline warning justifies its length.

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 8 parameters, no output schema, and annotations that already mark this as a non-read-only, non-destructive, idempotent operation, the description covers the key side-effect (re-baseline) and intended triggers. The schema handles parameter-level details; the description adds invocation context and a caution that prevents misuse. No critical gaps for correct selection/invocation.

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 covers 100% of parameters, so baseline is 3. The description adds the 'partial update' semantic, clarifying that only explicitly provided fields are modified, and repeats the feedUrl re-baseline consequence. Though the schema already documents feedUrl's re-baseline, the partial-update framing provides cross-cutting meaning not present in any individual parameter description.

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 ('Update') and resource ('RSS autopost feed'), clarifies scope with 'partial update,' and differentiates from create/delete/list siblings by naming the intended use cases (change, pause, re-point).

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?

Provides an explicit usage trigger: 'Use this when the user wants to change, pause, or re-point an RSS autopost feed.' However, it does not explicitly mention alternatives (e.g., create_rss_feed for new feeds, delete_rss_feed for removal), so the guidance is clear but not exhaustive.

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