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

Annotations already declare this is a non-read-only, non-destructive, non-idempotent write. The description adds meaningful behavioral context the annotations lack: authorization requirements per level and the atomic, all-or-nothing creation of inline key results. It does not warn about duplicate creation (relevant given idempotentHint=false) or the 10-key-result cap.

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 tight sentences with the core action front-loaded and no padding. The opening 'Create an objective' slightly restates the title, but the remaining content is dense and every clause carries information.

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 an 11-parameter mutation with no output schema and very low schema coverage, the description is only partially complete. Level semantics and atomic key results are covered, but the majority of optional fields (dates, owner, cycle, parent, strategic goal) are left unexplained, and nothing describes what the call returns.

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 only 18% across 11 parameters, so the description must carry weight. It explains the level enum semantics and their permission implications and clarifies inline keyResults behavior, which is useful. But cycleId, ownerId, parentId, startDate, endDate, description, and strategicGoalId receive no explanation anywhere, leaving most of the surface undocumented.

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 an objective') and adds a scope distinction by noting that key results can be supplied inline and are created atomically, which implicitly separates it from the create_key_result sibling. It stops short of naming the alternative explicitly, so the differentiation is inferable rather than stated.

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 clear precondition guidance for the level parameter: PERSONAL needs nothing extra, TEAM requires team membership, COMPANY requires admin rights. That is genuine when-to-use context. It does not cover when to create a standalone key result instead of inlining it, nor any exclusions.

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