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

Annotations already declare readOnlyHint, idempotentHint and destructiveHint=false, so 'Read-only' is redundant restatement. The genuinely additive bits are 'all at once' (implies an unpaginated full dump, useful for caching decisions) and the endpoint reference. It says nothing about the shape or size of the returned tag collection.

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 short sentences with zero filler: purpose first, then the reuse recipe, then the safety/endpoint note. Every clause carries information an agent would otherwise have to guess.

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 trivial one-optional-param read tool with rich annotations, the description covers what it returns conceptually ('the genre and mood tags ... all at once') and how to consume it. The only gap is that no output schema exists and the description does not say whether tags come back as flat strings or grouped by genre vs mood.

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% and there is a single optional 'account' parameter whose description already explains the mureka_list_accounts source and the single-account fallback. The tool description adds no further meaning, so the baseline 3 applies.

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 ('List the genre and mood tags Mureka understands') and scopes it with 'all at once', which separates it from the parameterized list tools like mureka_list_references or mureka_list_songs. An agent can identify it immediately 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?

Goes well beyond 'when to use': it names the exact downstream slots — the desc field of mureka_create_song_with_lyrics and mureka_remix_song, the mood/genre of mureka_upload_reference, and filtering in mureka_list_references. This is a discovery-then-reuse workflow made explicit, with no alternatives left to infer.

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