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

Annotations already declare the full safety profile (readOnly, idempotent, non-destructive, closed-world), so the bar is lower. The description adds useful signal that results are comparative across time ('winners and losers'), but says nothing about timeframe defaults, data freshness, or aggregation granularity.

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 short sentences, front-loaded with the core purpose before the routing hint. Every clause earns its place, though the Related line is terse enough to be slightly ambiguous about intent.

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?

An output schema exists and the single parameter is documented, so the description needn't explain return values. Combined with annotations covering safety, what's present is nearly sufficient for correct invocation; only the timeframe/scope defaults remain unstated.

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?

Only one optional parameter (siteId) with 100% schema description coverage, so the schema already carries the semantics and the description adds no further detail. Baseline 3 applies when the schema does the heavy lifting.

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 ('Shows') and resource ('tracked keyword positions') with the added scope 'now and over time, with winners and losers,' which tells an agent it returns a time-series comparison rather than a raw list. It nods at siblings via the Related line, but doesn't clearly distinguish itself from near-neighbors like get_search_performance or run_rank_check.

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 'Related: list_saved_keywords, save_keywords' line implies the surrounding workflow (view saved keywords, check their positions) but never states when to use this instead of get_search_performance or run_rank_check. Usage is inferable but not explicit.

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