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

Annotations already declare readOnly/idempotent/non-destructive, but the description adds essential behavioral context: it loads 'unchanged,' rejects placeholder/guessed IDs, and is not for starting new shoots or editing. This goes beyond the annotation flags without contradicting them.

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 four sentences, front-loaded with the core function, then usage rules, then exclusions. Every sentence adds necessary guidance with zero fluff or redundancy.

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?

Despite having no output schema, the description fully covers the tool's purpose, constraints, and relationship to alternatives (update_brief). With one well-documented parameter and rich annotations, no critical information is missing.

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 the schema parameter description already provides semantics: 'Real persisted brief ID to load unchanged. Do not use 0, guessed IDs...' The description reiterates these constraints but does not add significant new meaning beyond usage context, which is already covered by guidelines. Baseline 3 is appropriate.

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+resource: 'Load an existing persisted brief unchanged by a real positive brief_id.' It clearly distinguishes from siblings by explicitly stating when to call update_brief instead of looping on get_brief.

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 when-to-use conditions ('Only use when the user supplied that brief_id or after propose_brief/update_brief returned it') and when-not-to-use ('Never use this to start a new photoshoot' and 'call update_brief instead' for modifications). It names the alternative tool update_brief directly.

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