diff_graph_snapshots

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

Annotations already declare readOnlyHint, destructiveHint, idempotentHint. Description adds value by explicitly stating 'Read-only' and describing the output JSON structure, which is not in annotations.

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: first states function and output, second gives usage guidance, third declares read-only and output shape. No redundant words or repetition of schema/annotations.

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?

Given 2 simple string params and no output schema, description fully covers purpose, usage, and return fields. Agents have enough to decide when and how to use it.

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% (both 'base' and 'head' described). Description does not add extra information about parameters beyond the schema, which is acceptable. Baseline 3.

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?

Clear verb and resource: 'Compare two named graph snapshots and report deltas'. Specifies what it reports (counts, communities, top in-degree files). No sibling tool does exactly this; distinguished from compare_branches and snapshot_graph.

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?

Provides explicit usage context: 'track graph evolution over time without git as the axis (e.g. before/after a refactor, week-over-week health)'. While it doesn't mention when not to use, the context is clear and examples given.

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