verify_source_chain

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

Annotations already declare readOnlyHint=true, so the safety profile is covered. The description adds interpretive behavior (row-id gaps may indicate deleted audit rows) and the re-run workflow, which is useful, but it does not describe the return payload structure or any limits.

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 a [READ] tag and the core purpose, then a compact workflow note, then a clean Args list. No filler sentences; slightly terse but every line contributes.

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 tool with no output schema and annotations covering safety, the description supplies purpose, param meaning, and result interpretation. It is close to complete; only a note on the response shape or pagination would round it out.

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 0%, so the description carries the full burden and does so well: source is the tool name from list_audit_sources, and since/until are ISO timestamps bounding the range. All three parameters get clarifying meaning beyond their bare types.

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 action and resource: retrieving the chain head for a source's current events plus row-id gap detection. This is more than a restatement of the name. It doesn't explicitly contrast with siblings like verify_bundle or query_audit_events, but the purpose is clear enough for an agent to know what it does.

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 genuine usage context: record chainHead out-of-band and re-run later to detect changes, and it routes the agent to list_audit_sources to obtain the source value. However, it never states when to use this versus verify_bundle or query_audit_events, so guidance is implied rather than explicit.

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