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

Annotations already declare destructiveHint=true and readOnlyHint=false, so the safety profile is partly covered, but the description adds non-obvious behavior: the confirm=false preview / confirm=true apply pattern (an important safety gate for a destructive tool), required preconditions for conversion-based strategies, and target_roas percentage normalization. It does not explain reversibility of the change or whether an existing strategy is overwritten, but it goes meaningfully beyond the annotations.

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?

It is dense but front-loaded: the core action comes first, followed by the strategy enumeration, the tricky unit rule, the prerequisite, and the confirm semantics. Every clause earns its place, though the run-on strategy list and the parenthetical conditions make it slightly harder to scan than an ideal definition.

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 8-parameter destructive mutation tool, it covers the conditional requirements of the key parameters, the conversion-goal prerequisite, and the preview/apply gate, and an output schema exists so return values need not be described. It leaves out what happens to the prior strategy and any permission requirements, so it is strong but not exhaustive.

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 has to carry the parameter burden and it does: it defines the allowed strategy values, the conditional requirement of target_cpa and target_roas per strategy, the optionality and meaning of max_cpc (ceiling for MaxClicks), and the non-trivial unit convention for target_roas (350 or 3.5 both meaning 350%). This is exactly the value-add the schema lacks.

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+resource ('Sets a campaign's bid strategy') and then enumerates exactly which strategy values are accepted, with a per-strategy compatibility map (max_cpc only for MaxClicks, target_cpa required for TargetCpa, target_roas for TargetRoas). This distinguishes it from siblings like manage_bidding_strategies and manage_portfolio_bidding_strategy, which operate at different scopes.

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 prerequisite sequence for the four conversion-based strategies (list_microsoft_uet_tags → create_microsoft_conversion_goal), which is actionable when-to-use guidance, and explains confirm=false preview vs confirm=true apply. It does not name the alternative sibling tools (manage_bidding_strategies, manage_portfolio_bidding_strategy) or say when to use those instead, so it stops short of full routing guidance.

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