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

Annotations already declare readOnlyHint, openWorldHint, and idempotentHint, covering safety. The description adds behavioral context beyond these by stating that relationships are capped at one page, which is a significant limitation, and mentions the pagination alternative. It also clarifies the scope of included relationships and the role of MBIDs. No contradiction with annotations.

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?

The description is a single, dense sentence that front-loads the purpose and then lists content. It manages to include all key behavioral and contextual details without redundancy. While it is longer than average, every phrase contributes information, and the structure (purpose, contents, limitation/alternative) is logical. Not overly verbose.

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?

Given that an output schema exists (has output schema: true), the description need not explain return format. It covers the tool's inputs, what data is returned, the pagination cap, and the recommended alternative for heavy cases. Combined with the rich annotations, the description is fully complete for a read-only lookup tool.

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?

The schema description covers 100% of parameters (mbid and inc_relationships) with clear descriptions. The tool description adds minimal parameter-specific insight beyond reinforcing 'by MBID' and linking work-rels, but it does not need to because the schema already documents the parameters adequately. This meets the baseline of 3.

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 clearly states it retrieves a recording (a specific performance/track) by MBID, distinguishing it from the abstract work. It enumerates the specific data returned (length, credits, ISRCs, releases, works, relationships), making the tool's function unambiguous and differentiating it from sibling get_* tools.

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?

The description provides explicit usage context by identifying the tool as for recordings by MBID and includes an explicit alternative: 'for a heavily-covered recording call musicbrainz_browse_entities with target_type=recording and link.work.' It also implies a chaining pattern via 'work-rels — chain to musicbrainz_get_work', indicating when to use that sibling.

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