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

Annotations (readOnlyHint, openWorldHint, idempotentHint, destructiveHint) already indicate safe read. Description adds valuable context: return shape, mark_read side effect, and polling friendliness, enhancing transparency beyond 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?

Two dense sentences efficiently convey purpose, parameters, behavior, and an alternative. Well-structured and front-loaded. Could benefit from slight restructuring but overall concise.

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?

No output schema, but description adequately describes return shape (source, citation_uri, raw event payload) and supports polling and mark_read. Sufficient for a read-only tool with good annotations.

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 coverage is 100%, but description adds concrete examples (e.g., 'sec_8k' for type) and clarifications (ISO timestamp for since, effect of mark_read). Provides marginal additional value over schema.

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 it 'Pull fired events from your subscription feed' and lists specific returned fields (source, citation_uri, raw event payload), distinguishing it from sibling tools like list_subscriptions or search_within.

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 clear guidance on filtering (type, since), mark_read behavior, polling suitability, and even an alternative REST endpoint. Does not explicitly contrast with siblings but covers when-to-use adequately.

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