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

The description states 'Set mark_read:true to flag returned events read so the next call only shows newer ones,' which implies a persistent state change. This directly contradicts the annotation readOnlyHint=true, which declares the tool as read-only. The contradiction is serious enough to invalidate behavioral 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 front-loaded with the main purpose and consists of four tightly packed sentences. Every clause earns its place, including return payload details, filter examples, mark_read behavior, and an alternative HTTP endpoint. No wasted 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?

Despite lacking an output schema, the description explains what each alert carries (source, citation_uri, raw payload). It covers filtering, incremental reads via mark_read, polling suitability, and provides an alternative for scripts. Parameters like limit and unread_only are already covered by the schema, so the description is sufficiently complete.

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 descriptions for all 5 parameters. The description adds semantic value by explaining filtering with 'type (e.g. "sec_8k") and/or since (ISO timestamp)' and clarifying the effect of mark_read. This exceeds the baseline for full schema coverage.

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 opening phrase 'Pull fired events from your subscription feed' clearly identifies the tool's function with a specific verb and resource. It distinguishes itself from sibling tools like list_subscriptions (which enumerates subscriptions) and recent_changes (which tracks changes), making the purpose 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 clear usage context: 'Polls work fine' and explains how to use mark_read for incremental reads ('Set mark_read:true to flag returned events read so the next call only shows newer ones'). It also offers an alternative for direct scripts/dashboards via a URL, but it does not explicitly name sibling tools as alternatives or exclusions.

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