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

The description says mark_read:true flags returned events as read, implying a state modification. However, annotations declare readOnlyHint=true, indicating no modifications. This is a clear contradiction. The description also adds context about polling and alternative endpoints, but the contradiction undermines 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 concise (3-4 sentences), front-loads the main purpose, and every sentence adds useful information (purpose, fields, filtering, mark_read behavior, alternative access). No unnecessary words.

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?

For a read-only tool with no output schema, the description adequately explains return fields and parameters. However, the contradiction between mark_read behavior and readOnlyHint annotation makes the description incomplete, as the agent may be misled about the tool's side effects.

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 adds value by providing an example for type ('sec_8k'), explaining the effect of mark_read, and clarifying that since expects an ISO timestamp. This goes beyond the schema definitions.

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 pulls fired events from subscription feed, specifies returned fields (source, citation_uri, payload), and mentions filtering. It is specific about the resource and verb. While it does not explicitly distinguish from sibling tools, the purpose is unambiguous.

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 guidance on filtering by type and since, using mark_read, and notes that polling works fine. It also mentions an alternative endpoint for scripts. However, it does not explicitly state when to avoid using this tool in favor of siblings.

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