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

Annotations already declare readOnly=true, idempotent=true, destructive=false, openWorld=false, so the safety profile is covered. The description adds real behavioral value by disclosing what the result is composed of (github_releases notes plus forum/GitHub reports near the release window), which tells the agent the output is an aggregated synthesis rather than a raw changelog. It stops short of mentioning any gaps in coverage or freshness limits of those sources.

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 sentences, front-loaded with the core purpose, then the trigger, then a format hint. Every sentence carries information, though the trailing version-string sentence overlaps with what the schema already provides.

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 read-only, no-output-schema tool with fully documented params, the definition covers purpose, trigger, data sources, and input format. What is missing is minimal: no indication of result shape/size or how partial coverage is signaled, but an agent can call this correctly as written.

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% (all three params documented, including repo alias resolution and auto-inference), so the baseline is 3. The description's only added guidance is that version strings should match github_releases tags with or without a leading 'v', which largely restates the schema's own examples.

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+resource+scope: compares two Canton/Daml/Splice SDK versions and returns the changes between them, aggregating release notes and community reports. It also stakes out a domain boundary ('Canton-specific'), which distinguishes it from generic siblings like search_release_notes or get_sdk_changelog.

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 an explicit trigger condition: 'Use when a developer is planning an upgrade and asks what breaks moving from X to Y?' That is clear context and a concrete user intent. It does not, however, name alternatives or exclusions (e.g. vs get_sdk_changelog, check_deprecation, or find_security_patches), so routing between near-neighbors is still left to inference.

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