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

Annotations already declare readOnlyHint=true and destructiveHint=false. The description adds value by disclosing that setting mark_read:true flags events as read, affecting subsequent calls. It also notes the feed is persisted. No contradictions 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 tightly written sentences: first states purpose, second lists return fields and filters, third covers the side effect and alternative endpoint. No redundant words; all information 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?

Given the tool has 5 optional parameters, no output schema, and annotations covering safety, the description is largely complete. It explains return values, filtering, and side effects. Minor omission: the 'unread_only' parameter is not elaborated beyond the schema. Still adequate for effective tool selection and use.

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% with parameter descriptions. The description enhances understanding by providing examples (e.g., 'sec_8k' for type, ISO timestamp for since) and explaining the effect of mark_read. This goes beyond the schema's basic descriptions.

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?

Description opens with a specific verb+resource ('Pull fired events from your subscription feed') and details the return fields (source, citation_uri, raw payload). It clearly states filtering capabilities and distinguishes itself from siblings like 'recent_changes' by focusing on alerts from a subscription feed.

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 explicit context for when to use the tool (e.g., 'Polls work fine') and mentions an alternative access method (direct GET endpoint for scripts/dashboards). It explains the mark_read behavior but does not explicitly state when NOT to use this tool versus other options.

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