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

Annotations cover the safety profile (readOnlyHint=false, destructiveHint=false, idempotentHint=false), and the description adds genuinely non-obvious behavior: the suggestion is 'mined deep on the next scan' (a deferred effect, not immediate), the cap triggers a swap mode, and both operations are reversible. It also explains confirm's role via the secondary path. Minor gap: 'as the rail's Add/Swap does' is UI jargon an agent cannot resolve, and the return/receipt format is unspecified.

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 dense sentences, reasonably front-loaded with the primary action before the cap/swap and undo branches. The 'rail's Add/Swap' analogies and 'mined deep' phrasing consume space without adding agent-resolvable meaning.

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 mutation tool with no output schema and full schema coverage, the description supplies the missing pieces an agent needs: source of input, cap handling, and undo paths. Only the post-call result/pagination behavior is not covered, which is a minor omission.

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 meaning by tying swap_out_id to the 'at the cap' condition and clarifying it is usually swap_out.id from get_competitor_suggestions. root/app_id/confirm are left to the schema, which already documents them well.

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 ('Add a suggestion ... to the list') and identifies the source tool (get_competitor_suggestions) versus the sibling add_competitor, which adds competitors directly. An agent can tell what this does and where the input comes from without opening the schema.

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?

Explicit conditions: use swap_out_id when at the cap, undo an add with remove_competitor, undo a swap with restore_competitor. It names the alternatives and the trigger for each, leaving little to inference.

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