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

Annotations already declare readOnlyHint=true, idempotentHint=true and destructiveHint=false, so the safety profile is covered. The description adds real domain behavior on top: counts include contact-level assignments, and ai_send_block labels block sends while remaining readable, while ai_protected labels are human-managed and immutable via update_labels. The only missing behavioral detail is pagination (limit/cursor) and result ordering.

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 core purpose and then the label-flag semantics; every sentence carries information. Minor noise from the emphasis capitalization ('fully READABLE') and the slightly clipped opening noun phrase, but nothing is padded.

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?

With an output schema present, return-field explanations are unnecessary, and annotations carry the safety profile, so the flag semantics section is a genuine completion of domain context. However, for a paginated list tool with two fully undocumented parameters, omitting any statement about paging leaves a real operational gap.

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% for both `limit` and `cursor`; only type and bounds (1-50, maxLength 500) are encoded. The description says nothing about pagination, page size defaults, or how to pass a cursor back, so it fails to compensate for the low coverage as required.

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?

The description opens with a clear resource statement ('Org labels with counts') that, combined with the name, tells the agent this returns the org's label list enriched with usage counts. It distinguishes itself from create_task/list_tasks style tools by focusing on label metadata, but it never explicitly frames itself as the read-side counterpart to `create_bot`/`create_label`-style operations, so differentiation relies partly on the tool name.

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?

Guidance is implied rather than stated: the note that 'update_chat_summary'-style mutations are not possible here and that 'update_labels refuses to add or remove either kind' hints that this is a discovery/read step before mutation. There is no explicit 'use this when you need to enumerate labels before assigning' or any exclusion of alternatives such as `create_label`.

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