Breaking changes between two versions

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

Without annotations, the description provides significant behavioral detail: it reads real GitHub release notes and CHANGELOG fallback, covers every version in the range, and returns grouped notes newest first. It discloses the data source and output structure, which are non-obvious. Minor gaps: no mention of network dependency or potential failures, but the core behavior is transparent.

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 well-structured sentences: the first states what the tool does, the second provides usage timing and behavioral detail (source-grounded, fallback, grouping). No filler or redundant information; every clause 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?

Despite no output schema, the description clearly states the return format ('breaking notes grouped per version, newest first'). It covers purpose, usage context, data source, fallback behavior, and range semantics. It omits potential error conditions or performance implications, but for a read-only tool with 3 well-described params, the description is largely complete.

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 description coverage is 100%, so the baseline is 3. The description adds no parameter-level detail beyond the schema; it reinforces 'between two versions' but does not explain formats or edge cases. The schema already documents inclusive/exclusive bounds and package name examples, so the description adds no additional meaning.

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 uses a specific verb ('Get') and resource ('source-grounded list of BREAKING CHANGES for an npm package between two versions'), clearly distinguishing it from siblings like changelog_between (full changelog) and list_versions (version list). The scope is precise and immediately actionable.

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 states when to use: 'Reach for this BEFORE writing or reviewing any dependency upgrade / migration'. It also explains why it's the right choice ('defeats the model's stale, hallucinated migration knowledge'). It does not name alternatives directly, but the timing and context make the intended usage clear.

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