cyberchef_ecdsa_recover

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

The description goes well beyond the readOnlyHint/idempotentHint annotations by disclosing that up to TWO candidates may be returned, why low-S normalization makes that common, and that a wrong curve produces a plausible but unverifiable number. It also clarifies the operation is deterministic algebra, not a search, which is non-obvious behavioral 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 dense but every sentence earns its place: purpose, formula, output ambiguity, scope contrast, and exclusion of biased-nonce attacks. It is front-loaded with the core purpose and remains tightly structured despite covering subtle cryptographic behavior.

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?

Even without an output schema, the description tells the agent what to expect (up to two candidates), why ambiguity can occur, what inputs are required conceptually, and what failure modes exist (wrong curve, biased nonces). This is complete enough for correct invocation and interpretation for a specialized cryptographic tool.

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?

The input schema already documents every parameter thoroughly (curve enum, signature formats, hash width rationale), so parameter-level detail is well covered. The description adds mathematical meaning by giving the exact formulas involving z1, z2, s1, s2, and r, and notes that only the curve's order n is used—value beyond the schema's field-level descriptions.

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 ('Recover'), a precise resource ('ECDSA private key'), and the exact attack condition ('two signatures that reused a nonce, detected by a shared r'). It also distinguishes itself from single-signature ECDSA operations and from search-based approaches, so an agent can separate it from siblings without opening the schema.

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 defines when to use the tool: when two signatures share an r, and when not to use it: biased nonces require a lattice and are not implemented. It also contrasts this tool against the four single-signature ECDSA operations, giving clear routing logic against sibling tools.

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