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

Annotations already flag destructiveHint=true and openWorldHint=true, and the description adds real value on top: only the keyword list changes while other report settings are preserved, the 100-keyword cap, the no-duplicate rule for adds, and the timing of when new keywords receive positions. It doesn't cover failure modes such as removing keywords that aren't tracked, which matters given the destructive hint.

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?

Five short sentences, front-loaded with the core action and followed by constraints and timing. The second sentence slightly restates the first but earns its place by establishing that other settings are left untouched; overall there is little waste.

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 three-parameter mutation tool with a fully documented schema and rich annotations, the description supplies the missing behavioral layer: partial-update scope, deduplication, volume limits, and when results materialize. An agent has enough to call this correctly without an output schema.

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%, so the baseline is 3, but the description contributes semantics the schema cannot express: the per-report limit's practical meaning, the deduplication behavior of 'add', and the deferred-scoring consequence of both lists. This meaningfully clarifies how the two keyword arrays behave beyond their item constraints.

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 opens with a specific verb pair and resource: 'Add or remove keywords tracked by a location's Rank Tracker report.' That distinguishes it cleanly from read-only siblings like get_rank_tracker_report and list_rank_tracker_reports, and it names rerun_report as a related action.

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?

It makes the intended use obvious (change the tracked keyword set) and cross-references rerun_report as the way to get positions immediately rather than waiting for the scheduled run. It stops short of explicit when-not-to-use guidance or stating what happens if a location has no Rank Tracker report.

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