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

Annotations already declare readOnlyHint, idempotentHint, and openWorldHint, so the safety profile is covered by structured data. The description usefully adds what data comes back (current up/down, latency, vendor status) and that results are freshly monitored, but it says nothing about pagination, result size, or ordering — modest added value on top of rich annotations.

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?

Three short sentences, zero filler: what it returns, when to call it, and the optional parameter. The most decision-relevant information (the list contents) is front-loaded.

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 single optional-parameter read-only list tool with rich annotations but no output schema, the description conveys enough: result contents, trigger condition, and filter semantics. A brief note on result shape or behavior with an empty filter would complete it.

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 adds real meaning by giving concrete category examples (LLM, MCP, Search, Payments, Comms, Infra) that the schema lacks. It doesn't state what happens when the filter is omitted — presumably all vendors — which keeps it from a 5.

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+resource ('List the APIs and MCP servers Agent Daily monitors') and enumerates what's returned (up/down, latency, vendor status). It implicitly distinguishes itself from tool_status by being a listing/filtering tool, but never names the sibling, so it falls short of a 5.

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?

'Call before choosing a provider' gives explicit proactive guidance on when to use it, and the optional category filter is described with examples. There are no exclusions or named alternatives, which keeps it below a 5.

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