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

Annotations already indicate read-only, idempotent, non-destructive. Description adds value by describing return fields (source, citation_uri, payload) and the effect of mark_read. Could mention ordering or absence of events.

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?

Concise and well-structured. Each sentence adds information. Front-loaded with purpose. No redundant or unnecessary text.

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?

Describes return values sufficiently given no output schema. Mentions polling and alternative REST access. Does not cover ordering or behavior when feed is empty, but adequate for a simple read tool.

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 all 5 parameters with descriptions. Description adds real-world examples (type: 'sec_8k') and explains the practical use of mark_read for incremental reads. Exceeds schema alone.

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?

Clearly states the tool pulls fired events from a subscription feed. Uses specific verb 'Pull' and resource 'fired events'. Distinguishes from sibling 'list_subscriptions' which lists subscriptions, not events.

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 guidance on filtering by type and since, and explains the mark_read parameter. Mentions polling works and gives an alternative REST endpoint. Does not explicitly exclude scenarios or compare with siblings beyond implicit differentiation.

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