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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=false, so the safety profile is covered. The description adds genuinely new behavioral context about the result set: public source URLs are preserved while private sources are reduced to labels, which is non-obvious output behavior worth knowing.

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 sentences, front-loaded with purpose and scope, followed by use case and output behavior. Every clause earns its place and there is no redundancy or filler.

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, all-optional 4-parameter tool with full schema coverage and annotations, the description covers purpose, filters, and a key output behavior. With no output schema, a brief note on result ordering or pagination beyond the limit parameter would make it fully self-sufficient.

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 description coverage is 100%, and the description's "since a date, optionally by kind or affected record" merely restates the since, kinds, and about parameters without adding format or semantic detail. Baseline 3 applies when the schema carries the parameter documentation.

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?

Starts with a specific verb and resource ("List dated changes in agent tools and standards") and enumerates the change types the tool covers (new tools, renames, deprecations, breaking changes, new standards). This is clearly a changelog-style tool, distinct in scope from headlesson_search/get, though it never explicitly names those siblings.

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 a clear use context: "Useful for checking what changed after your training data," which tells the agent the intent and timing of the query. It stops short of stating when NOT to use it or pointing to a sibling alternative (e.g. search) for other lookups.

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