Recent changes

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

Annotations only carry readOnlyHint, so the description adds real behavioral context: no authentication required, newest-first ordering, the per-item shape, and the crucial limitation that history starts at Vigia's tracking start rather than being full release history. Auth and ordering are genuinely useful disclosures, though return format/pagination detail is absent and the read-only claim largely restates the 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?

Front-loaded with the change taxonomy, then scope rules, then the alternative and use case. The opening enumeration of change kinds is dense but each item earns its place as disambiguation; overall it is slightly long but not padded.

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 compensates by describing item fields (entity, kind, old/new values, detection time). Combined with scope rules, the auth statement, the history limitation and the sibling reference, an agent has everything needed to call it 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%, so the baseline is 3, but the description adds meaning the schema does not: how omitting name produces the global feed versus supplying ecosystem + name producing one entity's history. The enum values and limit bounds are left to the schema, which is fine.

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 (lists) and resource (changes Vigia detected) and enumerates the change kinds covered. It also distinguishes the tool's feed scope from list_versions, so an agent can tell it apart from siblings without opening a 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?

Explicitly frames when to reach for it ('find out what happened after your training data ends, or whether a dependency or model has just changed') and names the sibling to use instead for full release history (list_versions). The scoping rule (no name = global feed; ecosystem + name = single-entity history) further pins down usage.

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