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

Annotations already declare destructiveHint=true, so the safety profile is known; the description adds the mechanics — every embedded chunk for that source is removed, mRAG_search can no longer recall it, the count of deleted chunks is returned, and the operation is owner-scoped. That is meaningful context beyond the annotation, though it does not discuss irreversibility or confirmation requirements.

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?

Four short sentences, front-loaded with the action and resource, then the effect, then the constraint, then the return value. No filler and nothing repeated from the schema.

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 two-parameter destructive tool with no output schema, the description covers effect, scope, required input, ID provenance and return value. An agent has everything needed to decide and call 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 a constraint the schema cannot express: one of source_id or thread_id is required (schema lists zero required fields), and it identifies mRAG_list_sources as the source of valid IDs. That meaningfully clarifies parameter usage.

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+resource ('Remove indexed content from the user's knowledge base') and scopes it to deletion by source_id or thread_id, which unambiguously separates it from mRAG_search, mRAG_ingest and mRAG_list_sources.

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 tells the agent to obtain IDs from mRAG_list_sources and warns that it 'will not purge the whole index', which rules out a bulk-wipe interpretation. It stops short of naming an alternative tool for full-index resets or saying when deletion is inappropriate, so it is clear context rather than full when/when-not guidance.

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