build_agent_instruction

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

Annotations already declare readOnlyHint, idempotentHint, non-destructive and closed-world, so the safety profile is fully covered. The description's 'does not execute them' adds a modest clarification of the boundary but is largely implied by readOnlyHint and gives no detail on determinism, targetAgent behavior, or output shape.

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?

Two tightly written sentences: the purpose leads and the usage note follows. No filler, no repetition, and the key scope constraint is front-loaded.

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 no explanation. However, with 5 parameters, a 0%-covered schema, a nested context array with a kind enum, and the targetAgent enum, the description omits enough (especially targetAgent and the constraints-vs-requirements distinction) to be only adequate.

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 must carry parameter meaning. It names goal, requirements, and constraints (3 of 5), which is meaningful partial compensation, but leaves context and the significant targetAgent enum (8 target formats, default 'auto') entirely unexplained.

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 (assemble) and resource (execution instruction) and names the three input sources (goal, requirements, constraints). This clearly differentiates it from prompt-manipulation siblings like optimize_prompt or inspect_prompt, though it doesn't explicitly name any sibling.

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 a clear usage cue ('Use for multi-part tasks') and a boundary ('does not execute them'). It does not name alternatives among the sibling prompt tools or state when NOT to use it versus them, but the context is unambiguous.

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