lookup_token_by_symbol

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

Annotations already declare readOnlyHint=true and destructiveHint=false, indicating a safe read operation. The description adds valuable behavioral context beyond annotations: it specifies that results are based on 'similarity' (not exact matches), returns 'multiple potential matches', and is limited by 'TOKEN_RESULTS_LIMIT' from the Blockscout API. This enhances transparency about output behavior and constraints, though it doesn't cover rate limits or error handling.

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 highly concise and well-structured in three sentences: it states the purpose, clarifies the return behavior (multiple matches based on similarity), and specifies the limitation (TOKEN_RESULTS_LIMIT from Blockscout API). Every sentence adds essential information without redundancy, making it efficient and front-loaded for quick comprehension.

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 tool's moderate complexity (search with similarity matching), lack of output schema, and rich annotations (readOnlyHint, openWorldHint), the description is mostly complete. It covers key behavioral aspects like similarity-based matching and result limits, but doesn't explain the return format (e.g., what data fields are included) or potential errors, leaving some gaps in full contextual understanding.

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 100%, with clear descriptions for both parameters ('chain_id' as blockchain ID and 'symbol' as token symbol or name). The description adds minimal semantic value beyond the schema, only implying that 'symbol' is used for similarity-based searching. Since the schema already documents parameters well, the baseline score of 3 is appropriate, as the description doesn't significantly enhance parameter understanding.

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 the tool's purpose: searching for token addresses by symbol or name and returning multiple potential matches. It specifies the verb ('Search for'), resource ('token addresses'), and scope ('by symbol or name'). However, it doesn't explicitly differentiate from sibling tools like 'get_tokens_by_address' or 'nft_tokens_by_address', which prevents a perfect score.

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?

The description implies usage context by mentioning it returns matches based on 'symbol or token name similarity' and is limited to 'TOKEN_RESULTS_LIMIT' from the Blockscout API. However, it lacks explicit guidance on when to use this tool versus alternatives like 'get_tokens_by_address' or 'direct_api_call', and doesn't specify prerequisites or exclusions, leaving usage somewhat ambiguous.

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