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

The annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so safety is covered. The description adds genuine disclosure beyond them: the specific diagnostic categories checked and the return shape ('ok, warn or missing, why, and where to fix it'), which matters because no output schema exists.

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 the core purpose and the diagnostic checklist, with zero filler. The middle sentence is a long comma-separated clause that reads slightly run-on, but every element carries information.

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, single-optional-parameter diagnostic tool with no output schema, the description covers purpose, the four check categories, and the per-check result format. It stops short of saying what the agent should do with warn/missing results or how many checks are returned, but that is a minor gap.

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?

There is a single optional 'project' parameter with 100% schema description coverage, so the schema already explains the id-or-site form and the single-project default. The description adds nothing about that parameter, which is acceptable given the full schema coverage but earns no extra credit.

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 states a specific verb and resource ('Checks that tracking works') and enumerates exactly what gets checked: script visits, signups and payments reaching upTake, tracked links on posts, and the weekly report. The phrase 'before reading a 0' distinguishes it from the data-reading siblings (uptake_data, uptake_overview) without needing the schemas opened.

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 gives a clear trigger condition ('before reading a 0'), which tells the agent when to call this rather than trusting a zero metric. It lacks any explicit exclusion or named alternative, so an agent must infer that the diagnostic should precede rather than replace uptake_data.

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