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

Annotations already cover safety (readOnly, idempotent, non-destructive, closed-world), so the description adds genuine value by disclosing that results are a dated starter set rather than live data and that the return is metadata plus listening links only. It omits pagination or whatever happens when the query is empty, but the core behavioral caveats are stated.

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, each earning its place: purpose first, scope caveat second, return format last. Zero filler and front-loaded.

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 simple two-parameter read tool with full annotation coverage and no output schema, the description supplies the essential caveats (dated, non-exhaustive, links only). The remaining gap is the unexplained `limit` parameter and the apparent conflict between the fixed "four tracks" framing and the 1-12 limit range.

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%, so the description must carry the parameter burden. It clarifies that the query matches across song, artist and mood, which is real added meaning, but leaves `limit` entirely unexplained and creates tension by saying "four starter tracks" while the schema allows limit up to 12.

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 specific verb and resource ("Search four starter tracks by song, artist or mood") and immediately bounds what is searched ("dated starter selection, not a live or complete Spotify catalogue"). Sibling tools (get_creation_template, prepare_video_project) are unrelated in domain, so no explicit differentiation is needed, though none is offered.

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?

It gives clear context for when the tool applies (starter/seed tracks only, matched by song, artist or mood) and an explicit when-not (not for live or complete catalogue lookups). No named alternative is provided for the live-catalogue case, which keeps it below a 5.

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