## Estimate Cost

**post** `/compute/v1/small-molecule/library-screen/estimate-cost`

Estimate the cost of a small molecule library screen without creating any resource or consuming GPU.

### Body Parameters

- `molecules: array of object { smiles, id }`

  List of small molecules to screen.

  - `smiles: string`

    SMILES string of the molecule

  - `id: optional string`

    Optional identifier for this molecule

- `target: object { entities, bonds, constraints, 2 more }`

  Target protein with binding pocket for small molecule design or screening

  - `entities: array of object { chain_ids, type, value, 2 more }`

    Protein entities defining the target structure. Each entity represents a protein chain.

    - `chain_ids: array of string`

      Chain IDs for this entity

    - `type: "protein"`

      - `"protein"`

    - `value: string`

      Amino acid sequence (one-letter codes)

    - `cyclic: optional boolean`

      Whether the sequence is cyclic

    - `modifications: optional array of object { residue_index, type, value }  or object { residue_index, type, value }`

      Post-translational modifications. Optional; defaults to an empty list when omitted.

      - `CcdModification = object { residue_index, type, value }`

        - `residue_index: number`

          0-based index of the residue to modify

        - `type: "ccd"`

          - `"ccd"`

        - `value: string`

          CCD code from RCSB PDB (e.g. 'MSE' for selenomethionine, 'SEP' for phosphoserine)

      - `SmilesModification = object { residue_index, type, value }`

        - `residue_index: number`

          0-based index of the residue to modify

        - `type: "smiles"`

          - `"smiles"`

        - `value: string`

          SMILES string for the modification

  - `bonds: optional array of object { atom1, atom2 }`

    Covalent bond constraints between atoms in the target complex. Atom-level ligand references currently support ligand_ccd only; ligand_smiles is unsupported.

    - `atom1: object { atom_name, chain_id, type }  or object { atom_name, chain_id, residue_index, type }`

      Ligand atom reference. Atom-level ligand references currently support ligand_ccd entities only; ligand_smiles is unsupported.

      - `LigandAtom = object { atom_name, chain_id, type }`

        Ligand atom reference. Atom-level ligand references currently support ligand_ccd entities only; ligand_smiles is unsupported.

        - `atom_name: string`

          Standardized atom name (verifiable in CIF file on RCSB). Atom-level references to ligand_smiles entities are currently unsupported; use ligand_ccd instead.

        - `chain_id: string`

          Chain ID containing the atom

        - `type: "ligand_atom"`

          - `"ligand_atom"`

      - `PolymerAtom = object { atom_name, chain_id, residue_index, type }`

        - `atom_name: string`

          Standardized atom name (verifiable in CIF file on RCSB)

        - `chain_id: string`

          Chain ID containing the atom

        - `residue_index: number`

          0-based residue index

        - `type: "polymer_atom"`

          - `"polymer_atom"`

    - `atom2: object { atom_name, chain_id, type }  or object { atom_name, chain_id, residue_index, type }`

      Ligand atom reference. Atom-level ligand references currently support ligand_ccd entities only; ligand_smiles is unsupported.

      - `LigandAtom = object { atom_name, chain_id, type }`

        Ligand atom reference. Atom-level ligand references currently support ligand_ccd entities only; ligand_smiles is unsupported.

        - `atom_name: string`

          Standardized atom name (verifiable in CIF file on RCSB). Atom-level references to ligand_smiles entities are currently unsupported; use ligand_ccd instead.

        - `chain_id: string`

          Chain ID containing the atom

        - `type: "ligand_atom"`

          - `"ligand_atom"`

      - `PolymerAtom = object { atom_name, chain_id, residue_index, type }`

        - `atom_name: string`

          Standardized atom name (verifiable in CIF file on RCSB)

        - `chain_id: string`

          Chain ID containing the atom

        - `residue_index: number`

          0-based residue index

        - `type: "polymer_atom"`

          - `"polymer_atom"`

  - `constraints: optional array of object { binder_chain_id, contact_residues, max_distance_angstrom, 2 more }  or object { max_distance_angstrom, token1, token2, 2 more }`

    Structural constraints (pocket and contact). Atom-level ligand references currently support ligand_ccd only; ligand_smiles is unsupported.

    - `PocketConstraint = object { binder_chain_id, contact_residues, max_distance_angstrom, 2 more }`

      Constrains the binder to interact with specific pocket residues on the target.

      - `binder_chain_id: string`

        Chain ID of the binder molecule

      - `contact_residues: map[array of number]`

        Binding pocket residues keyed by chain ID. Each key is a chain ID (e.g. "A") and the value is an array of 0-indexed residue indices that define the pocket on that chain.

      - `max_distance_angstrom: number`

        Maximum allowed distance in Angstroms between binder and pocket residues. Typical range: 4-8 A.

      - `type: "pocket"`

        - `"pocket"`

      - `force: optional boolean`

        Whether to force the constraint

    - `ContactConstraint = object { max_distance_angstrom, token1, token2, 2 more }`

      Contact constraint between two tokens. Atom-level ligand references currently support ligand_ccd entities only; ligand_smiles is unsupported.

      - `max_distance_angstrom: number`

        Maximum distance in Angstroms

      - `token1: object { chain_id, residue_index, type }  or object { atom_name, chain_id, type }`

        Ligand contact token. Atom-level ligand references currently support ligand_ccd entities only; ligand_smiles is unsupported.

        - `PolymerContactToken = object { chain_id, residue_index, type }`

          - `chain_id: string`

            Chain ID

          - `residue_index: number`

            0-based residue index

          - `type: "polymer_contact"`

            - `"polymer_contact"`

        - `LigandContactToken = object { atom_name, chain_id, type }`

          Ligand contact token. Atom-level ligand references currently support ligand_ccd entities only; ligand_smiles is unsupported.

          - `atom_name: string`

            Atom name. Atom-level references to ligand_smiles entities are currently unsupported; use ligand_ccd instead.

          - `chain_id: string`

            Chain ID

          - `type: "ligand_contact"`

            - `"ligand_contact"`

      - `token2: object { chain_id, residue_index, type }  or object { atom_name, chain_id, type }`

        Ligand contact token. Atom-level ligand references currently support ligand_ccd entities only; ligand_smiles is unsupported.

        - `PolymerContactToken = object { chain_id, residue_index, type }`

          - `chain_id: string`

            Chain ID

          - `residue_index: number`

            0-based residue index

          - `type: "polymer_contact"`

            - `"polymer_contact"`

        - `LigandContactToken = object { atom_name, chain_id, type }`

          Ligand contact token. Atom-level ligand references currently support ligand_ccd entities only; ligand_smiles is unsupported.

          - `atom_name: string`

            Atom name. Atom-level references to ligand_smiles entities are currently unsupported; use ligand_ccd instead.

          - `chain_id: string`

            Chain ID

          - `type: "ligand_contact"`

            - `"ligand_contact"`

      - `type: "contact"`

        - `"contact"`

      - `force: optional boolean`

        Whether to force the constraint

  - `pocket_residues: optional map[array of number]`

    Binding pocket residues, keyed by chain ID. Each key is a chain ID (e.g. "A") and the value is an array of 0-indexed residue indices that define the binding pocket on that chain. When provided, these residues guide pocket extraction and add a derived pocket constraint during affinity predictions. That derived constraint remains separate from any explicit pocket constraints in target.constraints. When omitted, the model auto-detects the pocket.

  - `reference_ligands: optional array of string`

    Reference ligands as SMILES strings that help the model identify the binding pocket. When omitted, a set of drug-like default ligands is used for pocket detection.

- `idempotency_key: optional string`

  Client-provided key to prevent duplicate submissions on retries

- `molecule_filters: optional object { boltz_smarts_catalog_filter_level, custom_filters }`

  Molecule filtering configuration. Controls both Boltz built-in SMARTS filtering and custom filters.

  - `boltz_smarts_catalog_filter_level: optional "recommended" or "extra" or "aggressive" or "disabled"`

    Controls the stringency of Boltz's built-in SMARTS structural alert filtering, which removes molecules matching known problematic substructures. 'recommended' (default): applies a curated set of alerts balancing safety and hit rate. 'extra': adds additional alerts beyond the recommended set for stricter filtering. 'aggressive': applies the most comprehensive alert set — may reject viable molecules. 'disabled': turns off Boltz SMARTS filtering entirely; only custom_filters will be applied.

    - `"recommended"`

    - `"extra"`

    - `"aggressive"`

    - `"disabled"`

  - `custom_filters: optional array of object { max_hba, max_hbd, max_logp, 3 more }  or object { type, fraction_csp3, mol_logp, 8 more }  or object { patterns, type }  or 2 more`

    Custom filters to apply. Molecules must pass all filters (AND logic).

    - `LipinskiFilter = object { max_hba, max_hbd, max_logp, 3 more }`

      Lipinski's Rule of Five filter. Rejects molecules that violate drug-likeness criteria based on molecular weight, LogP, hydrogen bond donors, and hydrogen bond acceptors.

      - `max_hba: number`

        Maximum number of hydrogen bond acceptors. Lipinski threshold: 10

      - `max_hbd: number`

        Maximum number of hydrogen bond donors. Lipinski threshold: 5

      - `max_logp: number`

        Maximum LogP. Lipinski threshold: 5

      - `max_mw: number`

        Maximum molecular weight (Da). Lipinski threshold: 500

      - `type: "lipinski_filter"`

        - `"lipinski_filter"`

      - `allow_single_violation: optional boolean`

        If true, one rule violation is allowed (classic Rule of Five). Defaults to false (all rules must pass).

    - `RdkitDescriptorFilter = object { type, fraction_csp3, mol_logp, 8 more }`

      Filter molecules by RDKit molecular descriptors. Each descriptor is constrained to a min/max range. Only descriptors you provide are checked — omitted descriptors are unconstrained.

      - `type: "rdkit_descriptor_filter"`

        - `"rdkit_descriptor_filter"`

      - `fraction_csp3: optional object { max, min }`

        Min/max range constraint for an RDKit molecular descriptor

        - `max: optional number`

          Maximum allowed value (inclusive)

        - `min: optional number`

          Minimum allowed value (inclusive)

      - `mol_logp: optional object { max, min }`

        Min/max range constraint for an RDKit molecular descriptor

        - `max: optional number`

          Maximum allowed value (inclusive)

        - `min: optional number`

          Minimum allowed value (inclusive)

      - `mol_wt: optional object { max, min }`

        Min/max range constraint for an RDKit molecular descriptor

        - `max: optional number`

          Maximum allowed value (inclusive)

        - `min: optional number`

          Minimum allowed value (inclusive)

      - `num_aromatic_rings: optional object { max, min }`

        Min/max range constraint for an RDKit molecular descriptor

        - `max: optional number`

          Maximum allowed value (inclusive)

        - `min: optional number`

          Minimum allowed value (inclusive)

      - `num_h_acceptors: optional object { max, min }`

        Min/max range constraint for an RDKit molecular descriptor

        - `max: optional number`

          Maximum allowed value (inclusive)

        - `min: optional number`

          Minimum allowed value (inclusive)

      - `num_h_donors: optional object { max, min }`

        Min/max range constraint for an RDKit molecular descriptor

        - `max: optional number`

          Maximum allowed value (inclusive)

        - `min: optional number`

          Minimum allowed value (inclusive)

      - `num_heteroatoms: optional object { max, min }`

        Min/max range constraint for an RDKit molecular descriptor

        - `max: optional number`

          Maximum allowed value (inclusive)

        - `min: optional number`

          Minimum allowed value (inclusive)

      - `num_rings: optional object { max, min }`

        Min/max range constraint for an RDKit molecular descriptor

        - `max: optional number`

          Maximum allowed value (inclusive)

        - `min: optional number`

          Minimum allowed value (inclusive)

      - `num_rotatable_bonds: optional object { max, min }`

        Min/max range constraint for an RDKit molecular descriptor

        - `max: optional number`

          Maximum allowed value (inclusive)

        - `min: optional number`

          Minimum allowed value (inclusive)

      - `tpsa: optional object { max, min }`

        Min/max range constraint for an RDKit molecular descriptor

        - `max: optional number`

          Maximum allowed value (inclusive)

        - `min: optional number`

          Minimum allowed value (inclusive)

    - `SmartsCustomFilter = object { patterns, type }`

      Filter molecules by custom SMARTS patterns. Molecules matching any pattern are rejected.

      - `patterns: array of string`

        SMARTS patterns. Molecules matching any pattern are rejected.

      - `type: "smarts_custom_filter"`

        - `"smarts_custom_filter"`

    - `SmartsCatalogFilter = object { catalog, type }`

      Filter molecules using a predefined SMARTS catalog of structural alerts.

      - `catalog: "PAINS" or "PAINS_A" or "PAINS_B" or 11 more`

        Predefined SMARTS catalog to apply. PAINS, BRENK, ChEMBL, and NIH catalogs reject known problematic substructures.

        - `"PAINS"`

        - `"PAINS_A"`

        - `"PAINS_B"`

        - `"PAINS_C"`

        - `"BRENK"`

        - `"CHEMBL"`

        - `"CHEMBL_BMS"`

        - `"CHEMBL_Dundee"`

        - `"CHEMBL_Glaxo"`

        - `"CHEMBL_Inpharmatica"`

        - `"CHEMBL_LINT"`

        - `"CHEMBL_MLSMR"`

        - `"CHEMBL_SureChEMBL"`

        - `"NIH"`

      - `type: "smarts_catalog_filter"`

        - `"smarts_catalog_filter"`

    - `SmilesRegexFilter = object { patterns, type }`

      Filter molecules by regex patterns on their SMILES representation.

      - `patterns: array of string`

        Regex patterns applied to SMILES strings. Molecules matching any pattern are rejected.

      - `type: "smiles_regex_filter"`

        - `"smiles_regex_filter"`

- `workspace_id: optional string`

  Target workspace ID (admin keys only; ignored for workspace keys)

### Returns

- `breakdown: object { application, cost_per_unit_usd, num_units }`

  Cost breakdown for the billed application.

  - `application: "structure_and_binding" or "small_molecule_design" or "small_molecule_library_screen" or 3 more`

    - `"structure_and_binding"`

    - `"small_molecule_design"`

    - `"small_molecule_library_screen"`

    - `"protein_design"`

    - `"protein_library_screen"`

    - `"adme"`

  - `cost_per_unit_usd: string`

    Estimated cost per displayed unit as a decimal string, rounded up to 4 decimal places. This may include token-size multipliers or generation overhead; estimated_cost_usd is the authoritative total.

  - `num_units: number`

    Number of units shown for the estimate. For structure-and-binding, this is the requested number of samples. For protein and small-molecule design/screen endpoints, this is the requested number of proteins or molecules.

- `disclaimer: string`

- `estimated_cost_usd: string`

  Estimated total cost as a decimal string

### Example

```http
curl https://api.boltz.bio/compute/v1/small-molecule/library-screen/estimate-cost \
    -H 'Content-Type: application/json' \
    -H "x-api-key: $BOLTZ_API_KEY" \
    -d '{
          "molecules": [
            {
              "smiles": "smiles"
            }
          ],
          "target": {
            "entities": [
              {
                "chain_ids": [
                  "string"
                ],
                "type": "protein",
                "value": "value"
              }
            ]
          }
        }'
```