Create function

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

Annotations already declare non-destructive, idempotent, open-world behavior. The description adds real value beyond them: idempotency-key retention for recovery after an uncertain response, public URL exposure via webhook_enabled, and usage-based billing from the account balance.

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 the core purpose, then layered with prerequisites, recovery, webhook, and billing in five tight sentences. Each sentence carries distinct information with no filler.

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 14-parameter mutation with no output schema, the description covers the key operational concerns an agent needs: required inputs, runtime discovery, idempotency recovery, webhook exposure, and billing. It omits lifecycle/error semantics but is otherwise complete.

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% (baseline 3), but the description adds meaning: it names the three required fields and explains webhook_enabled's external-caller semantics beyond the schema's terse text. Minor inconsistency: it calls name/runtime_os_id/code required while the schema lists zero required params.

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 Firecracker Function"), clarifying the platform beyond the bare name/title. It does not explicitly differentiate from sibling creation tools like create_temp_vm or update_function, so it stops short of a 5.

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 one concrete prerequisite ("Read list_functions for current runtimes and limits") and a recovery instruction about the idempotency key. However it never states when to use this versus update_function or when not to call it, so usage is only partially guided.

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