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

Annotations already cover the safety profile (readOnlyHint, destructiveHint=false, openWorldHint=false). The description adds one genuine behavioral fact beyond them: pricing data is not cached, so results must be fetched live. It does not clarify whether the tool returns a URL, a rendered page, or structured plans/credits 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?

Two short sentences with no waste; the core purpose leads and the freshness caveat follows immediately. Every sentence earns its place.

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 parameterless, read-only lookup with no output schema, the description covers purpose and the live-data caveat adequately. The one remaining ambiguity is what the 'canonical page' actually returns, which is a minor gap for a task this simple.

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?

The tool takes zero parameters, so by the baseline rule parameter semantics default to 4. There is nothing in the schema for the description to compensate for.

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 ('Get the canonical page for current plans and credits'), which is clearly distinct from product_search or product_overview. It does not name a sibling or explicitly draw the boundary, so it stays at a strong 4 rather than 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?

'Prices are not cached in MCP' implies the agent must call this for pricing rather than relying on prior context, which is a useful implicit usage cue. However there is no explicit when-to-use vs when-not, and no comparison to the sibling tools, so the guidance remains implied.

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