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

Annotations already declare a non-destructive write (readOnlyHint=false, destructiveHint=false), so safety is covered. The description adds non-obvious behavioral context beyond annotations: that a project lives inside a client workspace and that its goal propagates to every child task. It still omits failure/duplicate handling and permissions, so it stops short of 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?

Front-loaded with purpose, then the guard, then the goal advice. Sentences are tight, though the trailing bare API-reference URL adds little for an agent already holding the schema.

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 mutation tool with no output schema, the description covers purpose, routing, and goal semantics well. The gap is that it frames the project as 'inside a client workspace' while 'client'/'client_id' are optional in the schema (only name is required), so the client relationship is left slightly unresolved.

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 only 50%, and the description meaningfully expands on 'goal' by explaining its inheritance effect, which the schema does not. However, it never clarifies the relationship or mutual exclusivity between the optional 'client' (fuzzy name/handle) and 'client_id' (UUID), which is the main ambiguity, nor touches name/deadline/brief_md. 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?

States a specific verb and resource ('Create a new project inside a client workspace') and concretizes it with examples (Website, Google Ads, Newsletter, Reporting). It is clearly distinguishable from siblings like create_client and create_task, so an agent can select it 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?

Explicitly gives the when-not condition and the alternative: 'Only create one when no existing project fits — call list_projects first.' This is a precise routing rule, not implied guidance.

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