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

Annotations already declare readOnly/idempotent/non-destructive/closed-world, so safety needs no restating. The description adds genuinely non-obvious context: the return shape (summary plus items with timestamps and source links), the cost model (upstream quota then $0.01 via x402), and the get_changes alias. It does not mention pagination or rate-limit behavior, so it stops short of a 5.

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?

Four tight sentences, zero filler. Purpose comes first, then when-to-use, then anti-patterns with named alternatives, then return/pricing/alias — ordered by what an agent needs to decide and then call.

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?

With no output schema, the description discharges that burden by stating the payload structure and item fields. Combined with full schema coverage and complete annotations, an agent has everything needed to invoke this correctly.

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% and every parameter already carries a disambiguating description (e.g. 'Not a provider id', 'Not a page token'). The prose only hints at windowing via 'in a window', adding no syntax or format detail beyond the schema, so the baseline 3 applies.

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?

Specific verb (List) plus the exact resource (recent outages, deprecation-page edits, model retirements, pricing-page edits across tracked AI/dev APIs). It explicitly names the two siblings it is not (check_api_status, get_digest), so the agent can discriminate without opening any schema.

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?

Gives both a positive trigger (see what changed in a window, explain a sudden integration error) and explicit exclusions with the correct alternatives for each case. Nothing about tool selection is left to inference.

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