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

Goes well past the annotations: it discloses upsert field-merge semantics (omitted fields left alone), idempotency (nothing duplicates), per-item result shape (created/updated with key, or failed with why), failure isolation ('a failed item doesn't stop the rest'), and the needs_confirmation/approvalId batch-approval flow. This is exactly the behavioral context annotations cannot convey.

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 the core create-or-update rule and matching key, then layers merge semantics, idempotency, results, and confirmation. Dense but every sentence carries operational information; slightly long, though nothing is padding.

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 batched mutation with no output schema and three params, the description covers creation, update/merge, idempotency, partial-failure behavior, return shape, and the confirmation/approval round trip. An agent has everything needed to call and interpret it 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 67%, and the description compensates by explaining the `url` match semantics (creates vs updates), that `statusName` is by name with a pointer to compass_statuses_list, and that omitted fields are preserved. It does not clarify the remaining nested item fields (tags, experiment, workflowPageId) beyond schema, but adds real meaning over the raw schema.

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 and resource ('Create or update up to 100 changes in one call'), names the matching key (`url`), and defines the upsert rule against it. An agent can distinguish this batch upsert from siblings like compass_links_create or compass_pages_create without opening a 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?

Gives concrete usage context: rerun with identical urls to stay in sync, statuses come by name via compass_statuses_list, and 'Summarize what you're about to bring in before calling.' It does not explicitly name when to prefer this over other creation paths, so it stops short of 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.