set_helius_api_key

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

The description goes beyond annotations by detailing internal URL construction, input validation (rejects URLs to prevent injection), process-memory persistence, and precedence over other configs. It also warns agents not to echo the key, adding critical security context.

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?

The description is well-structured with sections and front-loaded key info. Slightly long but every sentence earns its place; could be trimmed very slightly but remains clear and complete.

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?

Given the single parameter and no output schema, the description covers all aspects: purpose, usage, security, persistence, agent behavior, and source. No gaps are evident.

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% with a rich description. The tool description adds further meaning: explains UUID format, source, internal usage, and security implications, significantly enhancing the schema's own description.

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?

The description clearly states it sets a Helius API key for Solana RPC reads at runtime without restart. It specifies the canonical URL construction and distinguishes itself from other tools by focusing on runtime configuration.

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?

Provides explicit guidance on when to use (when user pastes key in chat) and where to get the key (https://dashboard.helius.dev/). Mentions it's designed for demo mode but works everywhere. However, no explicit exclusions or alternatives are named.

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