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

Annotations already disclose destructiveHint=true and idempotentHint=false; the description adds non-derivable context, notably 'No generation or charge' (cost profile) and the retry-after-lost-response procedure, which reinforces the non-idempotent behavior. It does not explain what the destructive hint actually destroys (e.g. an existing pinned DNA), which keeps it from a 5.

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, front-loaded with the core action, followed by the retry caveat and the cost disclaimer. Every sentence carries distinct information with no filler.

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?

An output schema exists, so return values need not be described, and the single parameter is fully covered by the schema. The description supplies cost, timing-window, and retry semantics, but leaves the 'pin window' undefined and the destructive consequence of re-pinning unexplained.

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?

Only one parameter, and the schema already documents projectId at 100% coverage including its source ('returned by studio_projects_list or studio_video_start'). The description adds nothing about the parameter, 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 precise verb+resource+target: pinning the artist's currently published DNA to a specific project. This clearly separates it from siblings like studio_artist_dna_write (which edits DNA) and studio_project_artist_presence_set (which sets artist presence). It does not explicitly name a sibling, so it stops short of a 5.

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 real operating context: the pin happens 'once, within its existing pin window', and the caller should 'read project state after a lost response before retrying'. That is clear when-to-call and how-to-recover guidance, though no alternative tool is named and no explicit when-not condition is given.

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