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

Annotations already declare readOnly, idempotent, non-destructive, so the safety profile is covered. The description adds non-obvious context beyond that: chronological ordering of results, a developer-tier auth requirement, and the important caveat that free evaluation returns a fixed training-set sample rather than live data.

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?

Four short sentences, each carrying distinct information, with the core action and ordering front-loaded before the id source and access caveats. Nothing is repeated from annotations or schema.

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?

With no output schema, the description never indicates what a "recorded change" entry actually contains (old vs new value, timestamp, actor), which is the main thing an agent needs to use the result. Pagination is left entirely to the schema's cursor parameter, leaving a notable gap for a history-listing 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 coverage is 75% and limit/cursor/user_request are already well documented in the schema, so the baseline is high. The description still adds real value by naming the provenance of the otherwise bare `id` string (take it from get_projections), which the schema does not say.

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?

States a specific verb and resource: retrieving every recorded change to a single projection, with an explicit ordering ("oldest first"). It is distinguishable from siblings like compare_lines or get_changes, though the name/description slip between "line" and "projection" terminology without clarifying they are the same entity.

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?

"Use an id from get_projections" explicitly routes the agent to the sibling that supplies the required identifier, and "Developer required" plus the free-evaluation note set expectations about access tier. It stops short of saying when to prefer this over compare_lines or get_changes, so the exclusion side is implied rather than stated.

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